Frequently asked questions.
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Preparing and reviewing a filing
How long will preparing a filing take?
The time depends on your prepared figures and filing route. You can save a draft, return later and review every document before submission.
Can I pause a filing and return later?
Yes. Saved filing inputs let you resume the supported draft. Review restored figures, dates and any allocations before continuing.
Can I change a draft before submitting?
Yes. Change your inputs and review the regenerated documents before approving the filing. An active annual subscription includes supported filings and amendments for the same company.
Can I download my prepared filing documents?
Yes. Download the supported CT600, accounts and tax computation files for review and your records. Available documents depend on the filing route, including whether accounts are generated or supplied by you.
Finding supported filing features
Which features support long accounting periods, different HMRC dates and CT600 amendments?
The Features catalogue explains supported long accounting periods, different HMRC dates and CT600 amendments, with links to the steps for each route. Check the scenario and organisation limits before starting. If you have already filed one return, use the separate remaining-return or amend-first/file-second guide.
Practice plans and company allowances
Who are Practice plans for?
Accountants, bookkeepers and agents who file for more than one company. Instead of a separate subscription per company, one annual plan covers a pool of companies and your whole team.
What counts as a company against my limit?
Each distinct company you submit a filing for uses one slot for the subscription year. Adding a company, preparing a return, or re-filing a company you have already filed for that year does not use another slot.
Why is Practice 5 more per company than Practice 10?
The larger plans are better value per company, so Practice 10 works out cheaper per company than Practice 5. If you expect to file for close to 5 companies, Practice 10 is usually the better buy.
What happens when I use all my slots?
You can choose more than one of the same Practice plan at checkout. Those units renew and cancel together. For example, two units of Practice 10 give you 20 company filing slots. You can add another plan later from your Team page. That new subscription has its own renewal date and slots. Cancelling renewal keeps your plan available until the end of the year you have paid for.
Can my team help without extra cost?
Yes. Team members are unlimited on every Practice plan. The group admin manages billing and invites, and members can add companies, prepare returns and submit.
What is included in each filing?
Everything needed to submit: the CT600, iXBRL accounts and the tax computation, to HMRC and Companies House or either on its own, with unlimited revisions before you submit.
What if I only file for one company?
A single eligible company can use a personal plan. Compare the current dormant and active micro-entity prices, including VAT, on the pricing page.
Choosing CT600 software
What makes good CT600 software for a small business?
Choose software that matches your accounts standard, filing destinations, period dates and required claims. Check imports, amendments, long-period returns, document previews and the total annual price including VAT. Compare the supported scenarios rather than the number of advertised features.
Is #Simple CompanyTax on HMRC’s software supplier list?
SimpleCompanyTax is listed as SimpleCompanyTax on HMRC’s Corporation Tax commercial software supplier list for CT600 production/submission, iXBRL documents and self-filers. A listing is not an HMRC recommendation or endorsement.
Where can I see all supported CT600 and accounts features?
The Features catalogue groups imports, periods, amendments, accounts, reliefs and supplementary pages. Each feature states its supported scenarios and links to a detailed guide. The organisation directory explains which route applies to your company, charity or club.
Can accountants manage clients, team members and several Practice plans?
Yes. Practice workspaces support unlimited team members, invitations, company access and supported company moves. You can buy multiple units of a plan at checkout or add another plan later. Plans added later have their own renewal dates. New-purchase Practice prices exclude VAT.
What is the best CT600 software in 2026?
There is no single best CT600 software for every company. Match the software to your accounts type, where you need to file and how many filings you expect in a year. For eligible micro-entity and dormant companies with prepared figures, #Simple CompanyTax costs £10 +VAT or £25 +VAT per company, per year, with unlimited filings and amendments for that company, including both returns of a long period and other accounting periods. WeFile and Tax Optimiser also offer FRS 102 accounts. The #Simple CompanyTax comparison lists published prices and scope for 11 suppliers, checked 17 October 2026.
What is the cheapest CT600 software in 2026?
Of the published prices we checked on 17 October 2026, Tax Optimiser was lowest for one trading accounting period at £10 + VAT, and Taxley was lowest for a dormant return at £9.50 with no VAT to add. FreeAgent is free for some NatWest, RBS, Ulster Bank and Mettle customers. #Simple CompanyTax is £10 +VAT for a dormant company and £25 +VAT for a trading micro-entity, per year. That price includes unlimited filings and amendments for the company, including both returns of a long period and overdue earlier periods. Compare the total for all the filings you need.
How does #Simple CompanyTax compare with WeFile?
WeFile charges £25 + VAT per trading filing and £15 + VAT per dormant filing, and charges each amendment again as a new submission. #Simple CompanyTax charges £25 +VAT per trading micro-entity and £10 +VAT per dormant company, per year, with unlimited filings and amendments for that company, including both returns of a long period. WeFile also supports FRS 102 accounts, which #Simple CompanyTax does not. WeFile prices checked 17 October 2026.
How does #Simple CompanyTax compare with TinyTax?
TinyTax Solo is £59 + VAT per year and its dormant plan is £20 + VAT per year. #Simple CompanyTax is £25 +VAT per trading micro-entity and £10 +VAT per dormant company, per year. Both file the CT600 to HMRC and accounts to Companies House, support long periods and amend returns first filed elsewhere. TinyTax prices checked 17 October 2026.
Is there free CT600 software now HMRC’s filing service has closed?
HMRC closed its free File your accounts and Company Tax Return service on 31 March 2026. From 1 April 2026 HMRC directs companies to commercial software, and paper returns are accepted only in limited cases. FreeAgent includes CT600 filing free for customers with an eligible NatWest, RBS, Ulster Bank or Mettle account. Most other suppliers charge a fee, and several let you prepare a return free before paying. #Simple CompanyTax lets you preview your documents without card details.
Which CT600 software prepares the CIC34 report for a community interest company?
#Simple CompanyTax prepares the CIC accounts and CIC34 report as a package for you to upload to Companies House, and files the CT600 to HMRC. Tax Optimiser also prepares the CIC34 as a PDF for you to file. WeFile and TinyTax state that they file only the CT600 for a CIC, with the accounts filed separately. Checked 17 October 2026.
Do CT600 software prices include VAT?
Often not. WeFile, TinyTax, Tax Optimiser, Taxpipe, CT600Filing and Easy Digital Filing publish prices plus VAT. Taxley states there is no VAT to add. #Simple CompanyTax shows £10 +VAT and £25 +VAT, with tax calculated at checkout. If your company cannot reclaim VAT, compare totals including VAT.
Supported organisations and filing routes
Is company interest trading or non-trading on the CT600?
The treatment depends on the loan relationship and what it is used for. Borrowing for the trade can produce trading interest expenses. Bank interest is usually non-trading for a company that does not trade in lending. You supply the treatment choice.
How far back can I file an overdue CT600 with this service?
#Simple CompanyTax supports periods starting on or after 1 April 2015 within its filing scope. This software limit does not remove an older filing obligation. Use the actual dates and review both returns for a long period.
Where can I compare the company and club filing routes?
The Who we support directory groups limited companies, charities, community organisations and members’ clubs. Each page explains the supported return, whether we prepare accounts or you supply them, and where the filing is sent.
Can I file both my CT600 and Companies House accounts?
Yes, for an eligible micro-entity filing. Review both document sets and choose the filing targets you need.
Can I file when my company has associated companies?
Yes. Associated-company inputs are supported for the Corporation Tax calculation. Group relief and consolidated accounts are outside the service.
Why can first company accounts need two CT600 returns?
First accounts can cover more than twelve months, but a Corporation Tax accounting period cannot. A supported long first period can therefore produce one set of accounts and two dated CT600 returns. Review both outcomes.
Can a company that only lets property use the service?
Yes, eligible property-only companies have a route using property income and expenses.
Can my company trade and let property?
Yes. The service supports both activities and asks for relevant allocation choices where needed.
What should I prepare for a property-only company return?
Have the prepared rental income, property expenses, company balance sheet and any relevant loss balances or tax adjustments ready. Property-only companies use the property route without inventing trading turnover.
Do I need to enter share capital?
No. The guarantee-company route uses members’ funds and does not ask you to invent share capital.
What if the guarantee company is a charity?
Use the charity route if the full-exemption filing is suitable. Charity accounts are supplied by you, and that route files with HMRC only.
Can a residents’ management company use the guarantee-company route?
An eligible non-charitable micro-entity company limited by guarantee can use that route. Prepare the figures belonging to the company and establish the treatment of any service-charge money before entering the accounts. The service does not make that accounting decision.
Will you prepare our charity accounts?
No. You supply the charity’s prepared accounts. This service prepares the supported return and sends the supplied accounts to HMRC.
Can we file a partly taxable charity return?
The incorporated and unincorporated charity routes support full-exemption claims only.
Do you file with the Charity Commission or Companies House?
No. Those filings remain separate from this HMRC-only charity return.
Does the charity CT600E route also submit our charity accounts to other regulators?
No. It submits the supported HMRC return with the accounts you supply. Preparing the charity accounts and filing with Companies House or a charity regulator remain separate tasks.
Can an unincorporated CASC file a partial exemption claim?
Yes. The unincorporated club journey supports full, partial and no-exemption treatments.
Is CT600E always included?
It accompanies an exemption claim. The club journey’s no-exemption treatment produces a taxable return without CT600E.
Are incorporated CASCs supported too?
Yes, through the separate full-exemption HMRC-only route using the club’s own accounts.
Where do taxable figures go in a partly exempt club filing?
Use Prepared taxable figures for the amounts prepared for taxation and the CT600E section for the relevant exemption disclosures. Do not enter the whole club surplus and then remove exempt activities again if they are already excluded from your prepared taxable figures.
Does the service include the CIC34 report?
Yes, the supported CIC flow prepares the CIC34 report alongside the accounts package.
Are the CIC accounts sent directly to Companies House?
You download the package and upload it through the Companies House CIC accounts service. This step is separate from the HMRC filing.
How do I know that both parts of the CIC filing are complete?
Check the HMRC outcome for the tax return and the separate Companies House upload confirmation for the accounts and CIC34 package. An HMRC receipt does not confirm that the Companies House upload has been completed.
Can an unincorporated club file a CT600 without supplying accounts?
Yes. The club filing journey lets you select Not Supplying Accounts and enter your Reason for omitting accounts. Your explanation is included with the CT600 to support box 90. You still provide the relevant prepared taxable figures. Use this option where omitting accounts is appropriate for your club, as the explanation does not itself establish permission to omit them.
Do we need a Companies House number?
No. The unincorporated club journey uses the club’s name and Corporation Tax UTR.
Will you prepare a balance sheet for the club?
No. The filing journey does not ask you to complete a limited-company balance sheet. Upload your own accounts or choose Not Supplying Accounts and give your reason.
Does uploading club accounts populate the taxable figures automatically?
No. If you upload accounts, enter your prepared taxable figures separately. The service does not extract taxable figures from the accounts or decide the treatment of mutual trading and exempt income.
Can an unincorporated golf club file a CT600 without supplying accounts?
Yes. The club filing journey lets you select Not Supplying Accounts and enter your Reason for omitting accounts. Your explanation is included with the CT600 to support box 90. You still provide the relevant prepared taxable figures. Use this option where omitting accounts is appropriate for your club, as the explanation does not itself establish permission to omit them.
Can you file a CT600 for an unincorporated golf club?
Yes. Use the dedicated club journey with the club name, Corporation Tax UTR and prepared taxable figures. Upload your accounts or choose Not Supplying Accounts and give your reason. A Companies House number is not required.
Do you prepare golf club accounts?
No. You can upload the club’s own PDF or iXBRL accounts, or choose Not Supplying Accounts and give your reason. We prepare the supported CT600 and the computation for taxable returns.
What if our golf club is a registered CASC?
The unincorporated CASC route supports full exemption, partial exemption and no exemption claim. CT600E is included for exemption claims. Incorporated CASCs have a separate full-exemption route.
Does all club income go into the taxable figures?
Enter the figures you have prepared for taxation. The service does not classify the club’s income or decide which amounts qualify for mutual trading or exemption.
What filing records should a new golf club treasurer ask for?
Gather the previous accounts, CT600, HMRC receipt and details of any balances carried forward. Confirm the club’s Corporation Tax UTR and the next period to file. If a long period had two returns, check both outcomes.
Does this include group relief?
No. Associated-company inputs are supported, but group relief claims and consolidated accounts are outside the advertised service.
Do I file one CT600 for all associated companies?
The service prepares separate filings for individual companies. It does not create a combined group return.
Should I combine associated companies’ figures before filing?
No. Prepare a separate filing using each company’s own accounts, dates and tax figures. Associated-company information is entered for the relevant individual calculation. This service does not prepare a combined group return.
Can I add CT600A to my company’s CT600 filing?
Yes. Eligible company filings support director and participator loan details and the supported repayment flow. You can review CT600A with the main return. Not every CT600A arrangement or relief is supported.
Should a later repayment replace the period-end loan figure on CT600A?
No. Keep the reportable period-end loan amount distinct from a later repayment. Where a qualifying Part 2 claim applies, enter the prepared repayment amount and date in the supported repayment fields and review the charge, relief and net tax.
Which exemption returns can I prepare with CT600E?
The incorporated charity and CASC route supports full exemption. Unincorporated CASCs can choose full, partial or no exemption in the club journey. The no-exemption treatment does not include CT600E.
Can a nil tax result replace the CT600E disclosure figures?
No. The claim still needs the relevant prepared disclosures. Gather the income, expenditure and asset figures asked for in the filing, follow the period dates shown and review them with the supplied accounts.
Does company accounts filing include charity or club accounts preparation?
No. The accounts preparation service covers eligible micro-entity private limited companies. Charity and unincorporated club routes file with HMRC only. Charities supply their accounts. Unincorporated clubs can supply accounts or give a reason for omitting them.
Is a confirmation statement included when I file micro-entity accounts?
No. Accounts, the CT600 and the confirmation statement are separate tasks. This accounts service does not file a confirmation statement. Check which task you need before starting.
Charity and CASC returns
Can I amend a club CT600 filed through another service?
Yes, for a supported unincorporated club return. Open the club and select Amend filing made elsewhere. Enter Period start and Period end, then select Continue. There is no Companies House period list. Check both return dates for a long period and use Change CT600 split date to edit First CT600 ends if needed. Enter corrected figures and any required allocations. On review, give the Reason for amendment. Filing goes to HMRC only. A long period produces two amended CT600s, so check both outcomes.
How do I file a CT600 for an unincorporated club or a partly exempt CASC?
When the club option is available, select Add company, then Not registered at Companies House from the dropdown. Add the club using its name and Corporation Tax UTR. For an incorporated club, select Registered at Companies House instead. Continue filing on the club dashboard card resumes the newest unsubmitted draft. If the newest filing has a submission record, it starts fresh without reopening an older draft. Start new filing on the club details page always starts fresh. A draft still being prepared cannot be edited until preparation finishes. In Club details and period, choose the accounts dates and charity or CASC status, then select Continue to figures and accounts. Date errors update as you correct the dates. Periods longer than 12 months and up to 18 months are supported. No exemption claimed appears first but is not preselected. Enter prepared taxable figures once in the Profit & loss and Tax adjustments sections. You can collapse and reopen either section. Leave optional adjustments blank when they do not apply, then use Choose accounts file to upload PDF (.pdf) or iXBRL (.html or .xhtml), up to 15 MB. The help beside How will you provide the accounts? links to HMRC’s accounts requirements for unincorporated clubs. Alternatively, select Not Supplying Accounts and enter Reason for omitting accounts beside the green box 90 badge. The help links to HMRC’s accounts guidance. Full, partial and no-claim CASC returns use the same club journey. Signatories enter Forename*, Surname* and Status* manually in the draft preview and filing credentials. You can correct the signatory’s name, title and status in the final filing window before submitting, without generating a new preview. Changes to figures, treatment, dates or accounts require a new review. The final declaration names the club and confirms your authority to submit and the accuracy and completeness of the return, without describing you as a director. In the final filing window, you can edit the Corporation Tax UTR and enter the Government Gateway details for this return. The edited UTR is remembered on the same filing, just as for incorporated companies. It does not change the saved club record. Filing history shows the reference used for each attempt. The personal subscription is £25 +VAT per year, with HMRC filing only.
Can a CASC claim exemption for one return and not the other in a long accounts period?
Yes, when the accounts period needs two returns. In Club details and period, choose Registered CASC, then Different treatment for each return under Exemption treatment, and pick a treatment beside each return’s dates. If one return is fully exempt, Prepared taxable figures names the other return’s dates and you enter figures for those dates only. The treatment for each return is the club’s own decision under HMRC’s rules.
Why is the wizard asking my charity for profit and loss figures?
The charity answer has not been chosen yet. In the company wizard, Special tax regimes starts on No. In the wizard for CIOs, SCIOs and charitable associations, Charity or CASC status starts on Neither. Change it to Charity claiming full exemption, or the CASC option for a CASC, and the next step shows the CT600E card instead of profit and loss figures.
Does a CASC need CT600E if it is not claiming exemption?
CT600E is the claim for exemption on all or part of a charity or CASC’s income and gains. A registered CASC making no exemption claim uses the taxable CT600 and computation route without CT600E. Registration alone does not mean the return has no tax to pay. When the club option is available, choose No exemption claimed in the club journey.
Do members’ golf clubs pay Corporation Tax on visitor fees?
Commercial fees from visitors and temporary members normally count as trading income. Related expenses, including a reasonable share of course overheads, may be deductible. Ordinary mutual trading and registered CASC exemptions are different treatments. A club’s rules and the nature of its receipts matter.
Does an unincorporated golf club need CT600E or an accounts explanation?
Unincorporated status alone does not require CT600E. A charity or registered CASC uses CT600E when claiming exemption on all or part of its income and gains. A club accounts explanation describes supplied PDF accounts or gives the club’s reason for omitting accounts. It is separate from the exemption claim. A fully exempt return can include an explanation for omitting its computation, while a partly taxable return still needs a taxable computation.
Why are draft documents available when a return check failed?
Generating documents and passing return checks are separate steps. You can inspect generated drafts even if a check prevents filing. Read Return checks to resolve on the filing record, review the relevant details and generate a fresh preview. Nothing has been submitted by a draft preview.
Can an unincorporated club attach PDF accounts to its CT600?
HMRC allows members’ clubs, CASCs and other unincorporated clubs covered by its accounts-format guidance to attach PDF or iXBRL accounts. Computations are normally iXBRL. Providing PDF accounts is different from omitting accounts, which needs an explanation in the return. Not entering a company-style balance sheet does not itself remove the accounts requirement.
How are an ordinary unincorporated club’s figures split over a long accounts period?
A club within Corporation Tax throughout an 18-month accounts period normally needs two CT600 returns. Ordinary trading profits are usually apportioned by time. Separate reliefs and event amounts can follow different rules, so not every box is divided by days. In the club journey, enter recurring taxable figures once. If one CASC return is fully exempt, enter prepared taxable figures only for the other return’s displayed dates.
Can I file for a charity or a CASC?
You can file for a supported incorporated charity, unincorporated charitable association, CIO, SCIO or registered CASC claiming exemption on all income and gains for a period of accounts of up to 18 months. For a charity or CASC registered at Companies House, choose Charity or CASC under Special tax regimes on step 1. The No option is for a standard UK trading or dormant company. Step 2 shows a Charity or CASC CT600E claim. Only charities are asked for a Charity Commission or OSCR number and the E180/E185 investment fields. Over 12 months requires two CT600 and CT600E returns, derived from one set of full-period figures. This is HMRC only. You upload your own accounts. Partly taxable returns, charitable trusts and charity-owned trading companies are outside this route. CIOs, SCIOs, unincorporated charities, clubs and CASCs use Not registered at Companies House when adding the organisation. Choose Charity claiming full exemption, Registered CASC or Neither under Charity or CASC status. Associations upload PDF or iXBRL accounts, or give a reason for omitting accounts.
My charity’s period of accounts is longer than 12 months. How do I file?
For up to 18 months of accounts, enter your figures once. We divide income, spending and disposals between two returns by days. Allocate legacy receipts in Amounts across your two returns. If the returns use different asset meanings, enter the second return’s additions in the optional Assets added during group, available even with zero balances. Upload full-period accounts once. For the Companies House company route, our service requires iXBRL above £6.5 million full-period income. This service policy does not apply to CIOs, SCIOs or unincorporated charities. Review both returns and check both receipts. A partly accepted pair uses the amendment process, with no automatic retry of only the rejected return.
How do I enter several legacies in CT600E?
A legacy is a gift left in someone’s will. Add the legacy income for the period together and enter one total in E88. In Date of the legacy, enter the latest legacy date. For example, legacies of £2,000 and £3,000 mean entering £5,000 and the later date. For a long period requiring two returns, also allocate the legacy income and enter each return’s latest legacy date in Amounts across your two returns.
Do I need a tax computation for a charity?
HMRC does not require a computation where CT600E confirms that all income and gains are exempt and have been or will be used for charitable or qualifying purposes. Annual accounts are still required. A partly exempt return needs the appropriate tax calculation and computation.
Can you file my charity’s accounts with Companies House?
No. This charity and CASC route submits CT600, CT600E and your uploaded accounts to HMRC only. Charity accounts and any trustees’ report must be prepared and filed separately with Companies House and the relevant charity regulator.
Will HMRC accept invalid uploaded iXBRL accounts?
HMRC may reject technical errors in uploaded iXBRL. Acceptance does not confirm every figure, accounting treatment or exemption is correct. We send your uploaded accounts unchanged and do not run Arelle or check their tagging. If all returns were rejected, correct and replace the file, review it and submit again. If either return was accepted, use an amendment. Do not resubmit a pending or unknown outcome.
Does the CASC £100,000 limit mean all that income is tax free?
No. The CASC registration income condition is separate from the trading and property tax exemptions. The relevant tax limits and all other conditions must be checked separately. Short accounting periods reduce the limits.
Intangible assets
How do I claim a non-trading loss on intangible fixed assets in box 265?
Enter your prepared non-trading realisation debit and credit. Review the current and brought-forward section 753 loss claims. The claim appears in box 265, while the loss arising in this return appears in box 830. Check the draft computation and both returns for a long period.
Is a software IP sale taxed as a chargeable gain?
A qualifying intangible fixed asset sale is usually dealt with under CTA 2009 Part 8. Use the prepared realisation credit or debit for its trade, property or non-trading route.
Selling intangible assets: corporation tax on realisation credits and debits →
How do I report an intangible asset sale on my CT600?
Enter the accounting disposal result and the prepared Part 8 credit or debit in their separate fields, then check box 640 on the draft CT600.
Report a sale or write-down of intangible assets on your CT600 →
Why is box 640 ticked on my CT600?
Box 640 is ticked when that return includes a positive Part 8 amortisation or impairment deduction, or when you answer Yes to the intangible asset sale or write-down question and select that return. The indicator does not change the tax due. Check both draft CT600s if your accounts need two returns.
Can I enter a full impairment of an intangible asset?
Yes. Include the accounting charge once in Depreciation and amounts written off assets, then enter the qualifying tax deduction in the intangible deduction field. Use this field for an accounts-based Part 8 impairment deduction. The deductible amount can be smaller than the full accounting write-off.
What if only part of the intangible accounting charge is deductible?
Enter the full accounting charge in Depreciation and amounts written off assets and the smaller prepared qualifying amount in the intangible deduction field. For a £2,000 charge and a £1,500 deduction, £500 remains added back for tax. Use the matching property fields for a property-business amount.
What if the intangible asset was disposed of or otherwise realised?
Enter the accounting profit or loss in the intangible disposal row and the prepared Part 8 credit or debit in its trade, property or non-trading field. Answer Yes to the event question for box 640. Do not relabel a realisation as an impairment deduction.
I already entered intangible amortisation. Do I enter impairment as well?
Use one combined qualifying deduction for amortisation and impairment in the same field, with the accounting charges included once in Depreciation and amounts written off assets. For £1,000 qualifying amortisation and £2,000 qualifying impairment, the combined entry is £3,000. Do not duplicate it in the property field.
Second CT600 when the first return is already filed
Why does my Corporation Tax show 25% when my profit is small?
Check the Filing purpose. File only the remaining CT600 taxes every figure you enter as earned in the second return dates alone. For a one-day return the profit limits fall to about £137 and £685, so a full year of profit is taxed at the 25% main rate. If HMRC has no CT600 yet for this accounts period, choose Standard return instead. If the first CT600 is already filed, enter figures for the second return dates only.
What does File only the remaining CT600 do?
It submits only the second CT600 of a long accounting period. It does not file, change or resend your first CT600. Use it only when HMRC already has your first CT600 with the full accounts and that return is correct. No accounts are attached to the second return, and box 90 gives HMRC the reason that the accounts went with the first return.
How do I amend only the second CT600 of a long accounting period?
Choose Amend filing made elsewhere, enter full accounts dates and select HMRC CT600, then the Amend only the second CT600 card. Its help icon explains the figures and attachments for this choice. Set First CT600 ends to the end of the first CT600. Confirm the remaining dates, enter corrected remaining-period figures and amend it.
Can I amend my first CT600 and file the second short-period return together?
Yes. If only the first CT600 is filed and its accounts need correcting to cover the full long period, use Amend filing made elsewhere, select HMRC CT600 and choose Amend the first CT600 and file the second as new. If the full tax span differs from your accounts, enter separate Corporation Tax dates. If the calculated first end differs from HMRC, open Change CT600 split date and edit First CT600 ends. Enter full-period figures and review both regenerated returns. We amend the first and file the second as new, attaching the full statutory accounts to both. HMRC determines acceptance separately for each return. We do not block submission using a locally calculated amendment deadline.
Can I submit only the second CT600 if the first return is already filed?
Yes. File the outstanding short period as a separate original return using its own dates. You do not need to resubmit the first return just to complete the second. Choose software that supports filing only the outstanding period.
Why can I not select File only the remaining CT600?
This filing purpose is available for HMRC CT600 only filings when the full accounts dates cover more than 12 months. Enter the full accounts dates, not just the remaining short period. If the full accounts period is 12 months or less, use Standard return. Changing the dates to 12 months or less switches the purpose to Standard return automatically. An older draft may still need you to select Standard return yourself. For periods of 12 months or less, the remaining-CT600 card stays visible but greyed out. Its help icon explains when it becomes available.
Do I attach accounts to the second CT600 if they were attached to the first?
An accounts-already-supplied route can apply when the first return included the full accounts covering both tax periods. The second return must explain why accounts are omitted. Active companies include their computation. Dormant returns use the reason “Company dormant” for omitting computations. This is not a general exemption from supplying accounts.
Do I need a second short-period CT600 if the company made a loss?
Yes, if HMRC requires a return for that period. Making a loss or having no Corporation Tax to pay does not remove the requirement to file. Use the short period figures and applicable tax adjustments.
Should I amend the first CT600 to cover the whole 13-month accounts period?
No. A Corporation Tax accounting period cannot exceed 12 months. File the outstanding second period separately. An amendment to the first return is for correcting that return, not for extending it to cover both periods.
Can a dormant company file only the second short-period CT600?
Yes, if HMRC requires the remaining return and the first CT600 included the full accounts. Select Dormant as the trading status and File only the remaining CT600 as the filing purpose. The help icons beside Trading status and Filing purpose explain the choices and link to HMRC and Companies House dormancy definitions, which use different tests. The first return is not resubmitted. Accounts are omitted because they were supplied with the first return, and computations are omitted using the reason Company dormant.
Can I use different software to file my second CT600?
Choose software such as SimpleCompanyTax to file only the second CT600 when the first was filed elsewhere. For eligible companies, our remaining-return option uses the short-period dates and handles accounts already supplied with the first return.
CT600 tax already paid and partial payments
Do I still need to file a CT600 if I have already paid Corporation Tax?
Yes. Paying the tax does not deliver a Company Tax Return. If HMRC has issued a notice to file, address that obligation even if nothing remains to pay. Payment and filing have separate deadlines.
Where do I enter tax already paid on a CT600?
Use box 595 for Corporation Tax paid for the return’s accounting period and not already repaid by HMRC. It is different from the tax liability and the balance still outstanding.
Can I file a CT600 with only part of the Corporation Tax paid?
Yes. Enter the relevant amount already paid in box 595 and report the full tax liability. The reconciliation calculates the balance still to pay. Filing does not extend the payment deadline or arrange a payment plan.
What should box 600 show if I have paid all the Corporation Tax?
For an ordinary return with no other credits, a payment equal to the tax liability leaves zero outstanding. For example, £3,800 liability and £3,800 in box 595 leave £0 in box 600. Check the HMRC account for later payments, interest or other charges.
Do I subtract HMRC refunds from tax already paid in box 595?
Yes. Exclude amounts already repaid by HMRC. For example, £2,000 paid for the period with £300 already refunded leaves £1,700 not repaid. Keep a reconciliation of the payments and refunds.
Can I include VAT, PAYE or next year’s Corporation Tax in box 595?
No. Box 595 is for Corporation Tax paid for the return’s accounting period. Do not include payments for other taxes or periods, restitution tax or coronavirus support scheme overpayments. Check an uncertain allocation with HMRC.
How do I enter tax already paid when there are two CT600 returns?
Identify the payment belonging to each return and enter each amount separately. Do not divide payments by days or repeat the whole payment on both returns. In SimpleCompanyTax, click + 595 Corporation Tax already paid under Tax adjustments. Enter each payment in 595 Corporation Tax already paid under Return 1 or Return 2, checking the dates shown.
What happens if tax already paid is more than the Corporation Tax bill?
For an ordinary return with no other credits, the excess is tax overpaid in box 605. A £4,000 payment against £3,800 liability gives £200 overpaid. Do not enter a negative box 600. A repayment is handled by HMRC and is not guaranteed to arrive immediately.
Can I enter Corporation Tax already paid in pounds and pence?
Yes. SimpleCompanyTax accepts payment amounts to two decimal places. For example, enter £2,000.25 as 2000.25. Keep the payment separate from your accounts profit and loss figures, which can also include pence. Enter the payment from your records.
Does entering box 595 pay HMRC or check my payments automatically?
No. Box 595 records the payment figure you provide. SimpleCompanyTax does not fetch your HMRC statement or make a tax payment through this field. Check your records and HMRC account, then confirm the figures and pay any remaining bill separately.
CT600 rounding and decimal places
Can I enter pence in my profit and loss figures?
Yes. Enter up to two decimal places in statutory profit and loss lines. Your accounts keep the pence and each stored category is rounded once to the nearest pound for Corporation Tax. Fields such as capital allowances and investment management expenses still require whole pounds. Tax payment amounts can include pence.
Why does my tax computation show a rounding line?
It reconciles operating profit in your accounts, which keeps pence, to operating profit calculated from whole-pound tax categories. You do not need a balancing expense. The computation labels the difference Rounding adjustment to operating profit and uses parentheses for a decrease. The reconciliation appears when a single-return bridge is available and there is a difference. The wizard shows these figures in the Corporation tax tooltip. For accounts longer than 12 months, figures entered once are rounded before allocation, while separately entered CT600 categories are rounded in each return.
How should I round figures for my CT600 filing?
Follow the instructions for the field and software. Where nearest-pound figures are requested, total each category first. For positive amounts, below 50p rounds down and 50p or above rounds up, so £1.49 becomes £1 and £1.50 becomes £2. #Simple CompanyTax keeps pence in statutory profit and loss entries and rounds each stored category once for tax. Follow each field’s precision instructions. Keep pence in the underlying records.
Does HMRC say to round CT600 turnover to the nearest pound?
The CT600 schema specifies a whole-pound format for turnover, but that format does not prescribe rounding up, down or at 50p. Do not describe the schema as an HMRC instruction to round turnover to the nearest pound. Follow the relevant field instructions and reconcile your accounts and computation.
Does FRS 105 specify a 50p rounding rule?
No. Paragraph 3.13(d) requires the rounding level to be shown in the financial statements. Paragraphs 8.4 and 8.6 address policy judgement and consistency. They do not prescribe a 50p CT600 rounding threshold or establish an ACCA-approved rounding algorithm.
Is Corporation Tax rounded to the nearest pound?
Tax amounts can include pence. #Simple CompanyTax uses nearest-penny rounding for calculated tax and marginal-relief amounts, producing two decimal places, with whole-pound return fields formatted separately. Rounding can happen to components before the final total, so it is not simply a whole-pound rounding of the final tax bill.
Why is my CT600 tax slightly different from Excel?
Excel can display whole pounds while still calculating with hidden pence. Compare the actual input values, tax adjustments, periods and rounding of individual tax components. A small difference may be caused by rounding, but a difference below £1 is not automatically harmless. Investigate an unexplained difference before filing.
Different CT600 and Companies House dates
Where do I enter the accounts, each CT600 and shared company details?
On Financial data, separate figures entry guides you through Accounts, CT600 1, CT600 2 when needed, then Shared details. Use Continue at the bottom of each set of figures. Each CT600 shows its ending date. Hover over or focus its navigation box to see the full dates. Shared details contains the balance sheet, employees and accounts details, entered once. Continue to Review & file briefly shows Review & Submit, then moves automatically to Review & file after checking and saving your figures. Preparing review… appears while the calculation or save finishes. Each accounts, CT600 and Shared details card has an Edit link that opens its own inputs.
Can I file to Companies House and HMRC together when my Corporation Tax dates are different?
Yes. Choose Companies House & HMRC CT600 and Enter figures separately. Enter the full statutory accounts figures and each CT600’s figures separately. With Enter my figures once and different tax dates, choose HMRC CT600 and file the Companies House accounts separately. A CIC can use separate figures for HMRC, with accounts and CIC34 filed through the Companies House CIC accounts service. File only the remaining CT600 continues to file just that return.
Do my CT600 figures have to add up to my accounts?
We do not check this. Where two CT600s cover the same dates as your accounts, their profit and loss figures normally add up to the accounts. They can differ where the Corporation Tax dates differ from the accounts dates. Tax adjustments are entered separately and do not change this.
Which accounts are attached when my CT600 dates differ?
HMRC receives the full statutory accounts for the accounts period that coincides with or overlaps the return. With Enter figures separately, these use the Accounts step. Each CT600 and computation use that return’s figures. If a second return lies wholly after the accounts, box 90 states that the accounts were sent with the other return.
CT600 figures different from the accounts period: which accounts do you send HMRC? →
Can I use actual figures for each CT600 instead of splitting by days?
HMRC normally uses time apportionment. It accepts a transactions basis where it gives a more accurate result. This typically applies where there are a few easily identifiable transactions and the trade is lumpy, such as property development. Choose Enter figures separately if you have prepared figures on an appropriate basis for each CT600. You choose that basis and the amounts.
Long period of account: time apportionment or actual figures for Corporation Tax? →
Can the first CT600 of a long accounting period be shorter than 12 months?
Yes. A Corporation Tax accounting period normally ends at the earliest relevant event in CTA 2009 section 10, so it can be shorter than 12 months. Check both dates in your HMRC account or CT603 notice. For a supported long period, the standard dates are calculated for you. Only if the first end differs from HMRC, open Change CT600 split date and edit First CT600 ends. The second return starts the next day and neither return may exceed 12 months.
My HMRC account shows different dates for my two Corporation Tax returns. What do I do?
Check both periods in your HMRC business tax account or CT603 notice. Enter the full accounts dates, use the separate Corporation Tax dates if needed, and leave the calculated dates as they are if they match HMRC. If the first end differs, open Change CT600 split date and edit First CT600 ends. The second CT600 starts the next day. Enter recurring figures once and confirm the requested capital and event allocations.
Two CT600s with different dates from HMRC: how to match them →
My HMRC accounting period does not match my Companies House year end. What should I do?
If the first Corporation Tax coverage exceeds 12 months, it needs two CT600 returns, so the first return ends before the company year end. Accounts longer than 12 months can still have one trading return if trading began later. A period can also end when trading stops. For a later-year mismatch outside those cases, call HMRC and ask it to align future accounting periods with the company year end. Use the dates HMRC confirms for the return you are filing.
HMRC Corporation Tax period differs from your company year end: what to do →
Which accounts do I attach to my first CT600 if trading started after incorporation?
Use the Corporation Tax dates shown in your HMRC business tax account and attach the full accounts from incorporation. Call HMRC before filing if you believe its dates are wrong.
First CT600 when trading started after incorporation: which accounts to attach →
Do I include costs from before trading started in my first accounts?
Yes. If the costs belong in your first accounts, keep them in the normal expense lines even when the HMRC Corporation Tax period starts later. Do not also enter them in Qualifying pre-trading expenditure. Add any amount that is not tax deductible to Disallowable expenses.
Can my CT600 end after my statutory accounts?
For a supported HMRC-only filing, you can enter Corporation Tax coverage that starts within your accounts and ends later. Keep the main Profit & loss figures for the statutory accounts. Under Days after your accounts end, enter only the additional dates, or choose No if there are no extra figures. If those dates cross the two-return boundary, enter and confirm their split. Keep the statutory balance sheet at the accounts end. Where return 2 lies wholly after that date, the full accounts go with return 1 and return 2 states that they accompany the other return. The displayed filing deadline is an estimate because a later relevant accounts period or HMRC notice may affect it.
Can my CT600 start before my statutory accounts?
For a supported HMRC-only filing, #Simple CompanyTax supports an earlier Corporation Tax start when the return and accounts have the same end date. Enter the main accounts figures for their statutory period, then enter any additional-day income, expenses and tax adjustments separately. Choose No if there are no additional figures. For two returns, confirm a split if the additional dates cross their boundary. The statutory operating figures stay separate, while the accounts tax charge follows the return.
Which dates should the Tax Calculation PDF show when my CT600 period is shorter than my accounts?
The Tax Calculation PDF and detailed Computation should identify the same Corporation Tax period as the CT600. Your annual accounts can cover a longer period. If the tax computation heading disagrees with the CT600, keep your correct accounts dates and contact support before filing. Generate and check a fresh draft after the correction.
Can my CT600 dates be different from my Companies House accounts?
Yes. The tax period and the annual accounts period can differ, for example after a dormant company starts trading or where one set of accounts covers two tax periods. Use the dates that follow from your actual tax position. Do not choose shorter dates just to leave out profit.
Can a Corporation Tax period end before the Companies House accounts end?
Yes, an event such as stopping a trade can end a tax period before the accounts year end. You must still check whether the company remains within Corporation Tax and needs another return. For supported HMRC-only filings, SimpleCompanyTax accepts an earlier end within the accounts period and tells you which dates the entered figures must cover.
Do I need to change my company year end to use different CT600 dates?
No, not just because the tax period legitimately differs. Keep the actual annual accounts period. If you want to change the annual accounts year end itself, use the Companies House process and address the resulting HMRC dates separately.
What should I do if the accounting period on my HMRC notice is wrong?
Compare the notice with your HMRC online account, accounts dates and activity records, then contact HMRC about the discrepancy. Explain the dates shown, the dates you believe apply and why. A software date edit does not itself correct a notice or cancel a filing obligation.
Where do I enter a different tax start or end?
In step 1, choose the full Companies House accounts period under Accounting period. Then choose HMRC CT600 or Companies House & HMRC CT600 under What are you filing? Tick My HMRC Corporation Tax period is different from my statutory accounts period. Enter both tax dates and complete the confirmations shown. Choose Enter figures separately to file both together with different tax dates. The tax period can start before the accounts if it ends on the same date. It can also end after the accounts if it starts within them. With Enter my figures once, answer the question about income, expenses or other tax figures for any additional dates. You do not need this option solely because a first accounting period is longer than 12 months. For a long tax span, we prepare two Corporation Tax returns. Each return that overlaps the accounts has the full accounts attached.
Does choosing a shorter tax period automatically reduce the figures I entered?
No. With separate figures, the accounts tab keeps the statutory P&L and each CT600 tab supplies its return. The product does not check whether the entries add up. With Enter my figures once, a later tax start after a period without trading uses the full approved accounts figures, including earlier costs. For an earlier tax end, we use the entered CT-period figures without reducing them for the shorter span. The attached accounts profit and loss then omits activity after that tax end, while the balance sheet stays at the accounts end. Existing short-period limits and two-return calculations still apply.
Can I amend a CT600 when its dates differ from my annual accounts?
Yes. An in-app amendment keeps the original accounts and tax dates. Split coverage regenerates both amended returns with saved allocations and computations. File only the remaining CT600 generates one return without accounts. For a second return filed elsewhere or within a full-period filing, choose Amend filing made elsewhere, then Amend only the second CT600. Enter full accounts dates and corrected remaining-period figures. Set First CT600 ends to the end of the first CT600. Amend both CT600 returns and Amend the first CT600 and file the second as new can also use separate Corporation Tax dates and a custom first end.
What does the box "My HMRC Corporation Tax period is different from my statutory accounts period" do?
Ticking it makes your CT600s cover the Corporation Tax dates you enter instead of your accounts dates. It does not change your accounts dates, your company year end or the dates HMRC holds for your company. Tick it only when your CT603 notice or HMRC business tax account shows different dates, for example after a dormant start. Leave it unticked for an ordinary accounts period longer than 12 months, because the two CT600s HMRC expects are already prepared from the accounts dates.
My CT600 was filed for the wrong dates. Can an amendment change them?
No. An amendment corrects a return HMRC already holds, for exactly the same dates. An amendment of a filing made with us keeps the original dates. An amendment of a return filed elsewhere must use the dates HMRC holds, to the day, or HMRC rejects it with error 1611. Tell HMRC which return has the wrong dates and which dates are right. Then file a new return for any dates HMRC holds no return for, and use an amendment only for a return whose dates are right.
Why is the different Corporation Tax period checkbox missing?
The checkbox appears when What are you filing? is HMRC CT600 or Companies House & HMRC CT600. It is absent for Companies House-only filing. To file both together with different tax dates, choose Enter figures separately. With Enter my figures once, choose HMRC CT600 and file the accounts at Companies House separately. A filing made elsewhere offers the checkbox with Amend both CT600 returns or Amend the first CT600 and file the second as new. Amend only the second CT600 uses First CT600 ends to set the remaining start in that journey. If an external amendment is shortened after separate dates have been entered, those controls stay visible so you can correct and reconfirm the dates or untick the option.
Does an earlier CT600 end change my payment and filing deadlines?
Check them separately. For companies outside instalment payments, the normal payment deadline is nine months and one day after the tax period ends. The return filing deadline also takes account of the relevant accounts period and the notice to file. Do not shift both deadlines by the same number of months.
Accounts and tax guidance
How do I read the Corporation tax due line on the review page?
It shows the taxable total profits the tax is charged on, the rate for the band, the band, the effective rate when marginal relief applies, and the limits applied to the return. For £100,000 of profit over 12 months it reads "On taxable total profits of £100,000 at 25.0% · marginal relief · effective 22.75% · limits applied £50,000 to £250,000". The rate depends on profit and the limits for the return’s dates, not on turnover. A filing with two CT600s shows the combined total without limits.
Why does the review page show 25% when my company gets marginal relief?
Between the limits, tax is first worked out at the 25% main rate and then reduced by marginal relief. The review card shows that rate and the lower effective rate after the relief. For £100,000 of profit over 12 months, tax at the main rate is £25,000, less £2,250 of marginal relief, so £22,750 is due, an effective rate of 22.75%.
Why is my Corporation Tax higher for a short accounting period?
For a return shorter than 12 months, HMRC reduces the £50,000 and £250,000 profit limits in proportion to its number of days. The same profit can then fall into marginal relief or the main rate. £30,000 of profit over 12 months gives £5,700 of tax. Over six months the limits are £25,068.49 to £125,342.47 and the tax is £6,069.86. The review page shows the limits applied to your return.
Can I file a CT600 as a close investment-holding company (box 4 code 2)?
Yes, for a supported active company. In Financial data, select Close investment-holding company under Company tax type immediately above Corporation tax in Profit & loss. In separate-figures mode, choose on the Return 1 tab. Return 2 shows the same choice, locked. The tax result updates when you change the choice. Hover over an option or focus it with the keyboard for help. The selected option has an info button with the full purpose test and CT600 box 4 code 2 details. Each CIHC return uses the full main rate, 25% from 1 April 2023, without small profits rate or marginal relief. One company tax type applies to both returns of a long period. This service cannot file returns whose company type differs between them. You or your accountant decide whether the purpose test applies.
Do I need a final CT600 before voluntary strike-off?
GOV.UK requires final statutory accounts and a Company Tax Return to HMRC before voluntary strike-off. Cessation ends the trading accounting period. Later taxable interest or receipts can require another return. The service does not support the section 198 election.
Voluntary strike-off and your final Corporation Tax returns →
How does a section 196 deduction reduce a post-cessation receipt?
A £1,000 qualifying post-cessation receipt less a £200 allowable section 196 deduction gives £800 in CT600 box 205. That is £152 at 19% if the small profits conditions apply, or £200 at the CIHC 25% rate from 1 April 2023, before other reliefs.
Post-cessation receipts and section 196 deductions: worked examples →
Do I need to file a CT600 for bank interest after ceasing to trade?
Taxable bank interest can keep your company within Corporation Tax after the trade stops. Report non-trading interest in CT600 box 170. A close company that simply holds bank deposits can be a CIHC, paying 25% from 1 April 2023 with box 4 code 2.
Bank interest after a company has stopped trading: do you still file a CT600? →
Is income received after a company stops trading taxable?
It can be. A qualifying receipt from the former trade that is not otherwise taxed can be a post-cessation receipt in CT600 box 205. Non-trading bank interest belongs in box 170. Money already taxed is not taxed again merely because it is collected later.
Income received after a company stops trading: is it taxable? →
What is CT600 box 4 code 2?
Box 4 is the company type. Code 2 means close investment-holding company. The return uses full main rates for each financial year, 25% from 1 April 2023, and boxes 329 and 435 stay blank.
Can a close investment-holding company claim marginal relief?
No. A CIHC cannot use the small profits rate or marginal relief. From 1 April 2023 it pays the full 25% main rate and files CT600 box 4 code 2. The ordinary profit thresholds do not create an entitlement for a CIHC.
Can a close investment-holding company claim marginal relief? →
What makes a company a close investment-holding company?
A close company is a CIHC unless throughout the accounting period it exists wholly or mainly for permitted purposes, or the limited winding-up exception applies. A CIHC uses CT600 box 4 code 2 and the full main rate, 25% from 1 April 2023.
Does a family investment company pay 19% or 25% Corporation Tax?
A family investment company that is a close investment-holding company pays the full main rate, 25% from 1 April 2023, and uses CT600 box 4 code 2. The name alone does not decide its status. Apply the statutory purpose test for each accounting period.
Does a family investment company pay 19% or 25% Corporation Tax? →
Can I file a CT600 for a period after my company stopped trading?
Yes, for the supported company filing route. Use separate accounts and CT600 figures if the accounts include earlier trading. Open Show all Profit & Loss options to enter Post-cessation receipts and Post-cessation deductions. If there is no trade or property business in a return, tick No trade or property business in this return. Ticking alone clears nothing. If conflicting income or capital entries exist, a notice names every field that Confirm and clear will remove, including capital allowances and balancing charges. Until you confirm, that return is worked out as if the box were not ticked. Keep the named fields and untick restores every entry unchanged. Next is blocked until you resolve the choice, but Save Progress still works and the notice returns when you resume. For two separate CT600s, the choice affects only the selected return. Once it applies, costs stay in the accounts but cannot create a trading loss, and brought-forward trading losses are not used automatically.
Do you support the section 198 election for post-cessation receipts?
No. The service files the ordinary receipt-period charge with your section 196 deduction. HMRC says a return electing to apply cessation-period rates may not be able to be filed online and directs you to your HMRC office for clarification.
Where do post-cessation receipts go on the CT600?
HMRC allows post-cessation receipts in CT600 box 205. In Profit & loss, select Show all Profit & Loss options above or below the table. Enter the gross amount in Post-cessation receipts and your section 196 claim in Post-cessation deductions, separately from ordinary other income. For two enter-once returns, confirm the allocation beneath the fields. The taxable receipt cannot fall below zero.
Can I choose different CIHC status for two CT600 returns?
No. Choose Company tax type once for the whole filing. It applies to both returns in either entry mode. In separate-figures mode, choose on the Return 1 tab. Return 2 shows the same choice, locked. This service cannot file returns whose company type differs between them. Each CIHC CT600 uses box 4 code 2 at the full main rate, 25% from 1 April 2023, without small profits rate or marginal relief.
What Corporation Tax rate does a close investment-holding company pay?
A CIHC pays the full Corporation Tax main rate, 25% from 1 April 2023, without small profits rate or marginal relief, and files CT600 box 4 code 2. Apply the statutory purpose test for each tax period.
Close investment-holding companies: Corporation Tax and CT600 box 4 →
Are investment appraisal costs allowable for Corporation Tax?
HMRC generally treats expenditure before a decision to acquire a particular investment as revenue and expenditure after that decision as capital. The expense must still satisfy the management expense conditions. A failed purchase does not change a capital cost into revenue.
What goes in box 850 on the CT600?
Box 850 reports only current management expenses left unrelieved in that return. It excludes the brought-forward balance and unused charitable donations. The final carry-forward pool is shown separately in the computation.
Can an investment company carry forward unused donation relief?
Yes, if the company has an investment business and made the qualifying donations for its purposes, eligible unused relief joins its management expense pool automatically. The investment business must continue for the next-period deduction. Exclude amounts already used or surrendered. For periods starting on or after 1 April 2017, the later claim can be whole, partial or nil, normally within two years after that period ends. Earlier periods use a mandatory deduction with the claim blank. On Financial data, Unused donation relief appears below a current Charitable donations amount above £0, after the long-period split panel. Choose Carried forward to reduce future profits (investment business only) when the conditions are met. Not carried forward is for a company that does not meet them. With no non-zero management figures, blank means Not carried forward. Management figures apply the treatment automatically. Read HMRC CTM08620 for the full conditions.
How do I enter management expenses in the CT600 filing wizard?
Open Tax adjustments and enter Investment management expenses beside the green 245 badge. The help tooltip explains that this total is already included in your costs. For a long accounting period, the splitter divides the same total between both returns. Confirm that allocation and enter any eligible opening excess balance. Check Opening, Maximum and Closing beneath each claim. Any Company deductions allowance shown has its own row for the relevant return.
How to enter management expenses in the CT600 filing wizard →
Can a property investment company claim management expenses in box 245?
A company with investment business can claim qualifying revenue management expenses against total profits in box 245. Capital costs and amounts otherwise deductible are excluded.
Management expenses of an investment company: CT600 boxes 245 and 850 →
Does box 4 code 7 change the Corporation Tax my company pays?
Code 7 identifies a property management company in box 4. It does not by itself change the calculation. Enter the company's trading and property figures in the appropriate sections.
Why is there no property management option under Special tax regimes?
A property management company is not a special regime in the filing wizard. Answer No under Special tax regimes on the first step and set Trading status to Active, because the form starts on Dormant. Then choose Property management company under Company tax type in Profit & loss on Financial Data. That files code 7 in box 4 of every CT600 in the filing, including both returns of an accounts period over 12 months. Code 7 does not change the tax, and the dormant journey does not offer it.
Is a grant turnover?
A grant supporting costs without paying for goods or services is generally outside turnover. A payment called a grant that actually pays for goods or services may be turnover. Use the classification in your prepared accounts.
Are grants to a community interest company taxable?
A community interest company does not receive a general Corporation Tax exemption just because it is a CIC. The purpose and nature of a grant still determine its treatment.
Do I pay tax on a grant I have not spent yet?
Spending the cash does not alone decide when a grant appears as income or whether it is taxable. If your prepared accounts carry an amount forward as deferred income, enter the balance in Accruals and deferred income, not Other income not taxable. When the accounts later recognise it as income, enter it in that period's income row and use the tax treatment you have determined for that amount.
How to account for a grant in micro-entity accounts under FRS 105 →
Does a capital grant reduce capital allowances?
A contribution from a public body normally reduces qualifying expenditure. Some private contributions may not, if the statutory conditions are met. Enter your prepared qualifying amount.
Capital grants and capital allowances: when a grant reduces your claim →
Are grants taxable for a limited company?
A revenue grant towards trading costs is normally a trading receipt. Capital grants may affect capital allowances. Use your company’s prepared accounts and tax treatment for the particular grant.
Are grants taxable for a limited company? Grant income and Corporation Tax →
Where do I enter a grant in my company tax return?
Enter the amount your accounts recognise this period in the income field that matches its source. Use Other trading income for the taxable part of a trade grant and the property rows for a letting grant. For recognised income your company treats as not taxable, use Income not falling under any other heading with the same amount in Other income not taxable. A deferred balance belongs in Accruals and deferred income, not a tax adjustment.
Grants on your CT600: where to enter taxable and non-taxable grants →
Does VAT count towards VAT registration turnover?
No. HMRC defines taxable turnover for VAT registration as the value of taxable supplies excluding VAT. Divide a VAT-inclusive standard-rated sale by 1.2 to find its value before VAT.
Where do I disclose a guarantee the company gave for a director?
Companies Act 2006 section 413 requires details in the accounts notes of guarantees entered into by the company on behalf of its directors. The note gives the guarantee’s main terms, maximum possible company liability, and amounts paid or liabilities incurred to fulfil it.
Does an overdrawn director’s loan go in the accounts note or section 455 tax?
They are separate. The accounts note reports relevant advances and credit with repayments and other particulars. Section 455 may charge a close company on a loan or advance to a participator that remains unpaid, subject to the statutory rules and relief. One does not replace the other.
Overdrawn director’s loan account: accounts note or section 455 tax? →
What must micro-entity accounts disclose about loans to directors?
Companies Act 2006 section 413 requires notes about advances and credit the company grants to its directors, including the amount, interest rate, main conditions and amounts repaid, written off or waived. The note also gives totals. It separately covers guarantees entered into for directors. A director lending money to the company is a different transaction.
What micro-entity accounts disclose about directors’ loans →
How do I add directors’ advances and guarantees to my accounts?
In Financial Data, open Optional notes to the accounts and choose + Directors’ disclosure. Use + Advance or Credit or + Guarantee for each record, choose + Previous-period figures if needed, then check the generated accounts.
How to disclose directors’ advances and guarantees in company accounts →
My accounts include income that is not taxable. How do I keep it out of my Corporation Tax?
Keep the full accounts amount in Income not falling under any other heading. In Tax adjustments, enter the part you treat as not chargeable in Other income not taxable. You can add an optional description. Review the computation and the remaining taxable amount in CT600 box 205.
Does Other income not taxable change my accounts?
The figures you entered do not change. The Corporation Tax charge may fall, increasing profit after tax or reducing the loss after tax. If tax was already nil, those figures stay the same.
Can Other income not taxable be more than my Income not falling under any other heading figure?
No. This adjustment removes part of that accounts income from taxable profits, so it cannot exceed the full income figure. Enter the full accounts amount in the Income section first. It cannot exclude turnover or another income category.
Do I have to explain why the income is not taxable?
HMRC expects details describing the income and why it is not taxable. A Description row appears under Other income not taxable once you enter an amount. It is optional and leaving it blank does not block filing. Any description you enter appears in the tax computation.
Does your service support CT600A and section 455 tax on director’s loans?
Yes. You can enter prepared whole-pound unpaid loan amounts for each borrower and return period. We calculate section 455 tax, generate CT600A and file it electronically with the CT600. This includes amended returns for trading, property and mixed companies. Qualifying loan repayments within nine months are supported through Part 2. Later relief, releases, write-offs and historical periods spanning different loan-tax rates are outside scope.
Is CT600A included in the annual filing price, and can I preview it before paying?
CT600A is included in the micro-entity subscription at £25 +VAT per year, with no supplementary-page fee. Generate a free draft preview to see the completed CT600A and tax computation before paying or submitting. The draft PDFs are watermarked.
Should I enter the closing director’s loan balance to calculate section 455 tax?
Enter your prepared amount for loans made in this CT600 period that remain outstanding. A closing balance may contain older loans already reported. The optional A75 figure is the total outstanding across all periods and does not calculate this return’s charge. HMRC’s loan fields take whole pounds, while tax is calculated in pounds and pence.
How much is section 455 tax on a director’s loan?
For a reportable loan made during 2025 that remains unpaid after the nine-month window, section 455 tax is 33.75% without relief. A £10,000 loan gives £3,375 tax. Historical rates differ. For loans from 6 April 2026 the statutory rate is 35.75%, but HMRC’s current online format still uses 33.75% until its planned 6 April 2027 update. HMRC gives amendment instructions for affected returns after that update. Full qualifying relief leaves nil net tax at either rate, but the notice does not expressly exempt fully relieved loans from amendments to the gross disclosures. Follow HMRC’s current service guidance linked in the article.
Where do I enter a director’s loan repayment after the period end?
In Financial Data, open Director’s loans and section 455 tax and choose Add loan repayment under the relevant borrower. Enter Amount repaid after the period end and Date of last repayment included. For several qualifying repayments on one account, use their prepared total and the last included date. This completes CT600A Part 2.
Does full repayment within nine months make section 455 tax nil?
Full qualifying repayment can offset the entire charge through section 458 relief. Partial qualifying repayment reduces it by the corresponding relief. CT600A still reports the gross charge in A20, relief in A45 and net tax in A80 and box 480. Ordinary Corporation Tax on profits is separate. Repayment and reborrowing restrictions can affect the qualifying amount.
How do I enter repayment relief when my first period has two CT600s?
Enter the prepared repayment against each relevant dated return in the director’s loans section. Each actual Corporation Tax period has its own repayment window. Loans and repayments are not divided by days. If one repayment relates to both returns, allocate its qualifying amount between them without claiming the same amount twice.
Where does director’s loan repayment relief appear on the CT600 PDFs?
The separate CT600A shows the repayment amount and date in A25, repayment totals in A30 and A40, gross tax in A20 and relief in A45. Net tax in A80 carries into box 480 of the main CT600. Full qualifying repayment makes A80 and box 480 zero. Box 600 can still show ordinary Corporation Tax outstanding. Generate a fresh preview after editing a repayment and check both dated returns for a long accounts period.
Can I amend a filed CT600 to add loan repayment relief?
Yes, through the supported amendment journey, subject to its existing eligibility and time limits. Add the qualifying Part 2 repayment to the relevant borrower and review the amended CT600A and computation. Under File this amendment to, tick HMRC so the CT600A goes with the amended CT600. Supported originals filed elsewhere can also be amended. Later Part 3 claims, releases and write-offs are outside this feature.
Which CT600 supplementary pages do I need?
It depends on your transactions. CT600A concerns close company loans and benefits to participators, B covers CFCs, foreign permanent establishments and mismatches, C covers group relief, D insurance and E charities and CASCs. Company size alone does not decide. Check the official forms and software support.
Do both first-year CT600 returns have the same filing deadline?
Normally yes where the full accounts period is no longer than 18 months: both are due 12 months after that full period ends. A later notice-to-deliver deadline can apply. Tax payment dates are separate.
What mileage rate applies to an employee using their own car?
HMRC publishes 55p per business mile for the first 10,000 miles from 6 April 2026, compared with 45p before that date. The rate above 10,000 miles is 25p. Use the rate for the relevant tax year, not company-car fuel rates.
Can a company deduct advertising gifts to customers?
A narrow exception can allow gifts bearing a conspicuous advertisement on the gift itself. Food, drink, tobacco and exchangeable tokens or vouchers do not qualify. Relevant gifts to the same recipient must cost no more than £50 in the company accounting period.
Is the pension annual allowance a cap on the employer-contribution benefit exemption?
No. The employment income exemption for an employer contribution to a registered pension scheme is separate from a possible personal annual-allowance charge. Tapering, the money purchase annual allowance and carry-forward can matter. Company tax deductibility is a separate test too.
Do finance-leased assets belong in Tangible assets?
Include finance-lease assets recognised under FRS 105 at net book value, with the lease liability separately in creditors. Ownership need not have transferred. This does not mean every rented asset qualifies or that a capital allowance is automatic.
Is a limited company always more tax-efficient than a sole trader?
No. Company tax, salary and dividend tax, National Insurance, other income and administration all matter. A dated example is an illustration, not a universal profit threshold for incorporating.
Is a director’s loan repaid before the year end still disclosed?
It may still need to appear in the accounts note. Companies Act 2006 section 413 covers advances and credit granted to directors and includes any amounts repaid. CT600A has separate rules: HMRC says a loan made and wholly repaid in the same accounting period generally does not need to be included there unless it was released or written off.
Does positive year-end retained profit prove an earlier dividend was lawful?
No. Consider distributable profits at the relevant date using the relevant accounts. Positive closing reserves do not prove an earlier payment was lawful, and a later loss does not retrospectively invalidate a dividend that was lawful when made.
Is DS01 the form for dormant accounts?
No. DS01 is a strike-off application, not an accounts form. Dormant accounts and dissolution are different tasks with different consequences and fees.
Accounts and computation details
How do I restate last year's comparative figures in micro-entity accounts?
Enter the corrected figures in the previous year column on Financial Data. You can also add a prior year adjustment note and show As restated on that column in Optional notes to the accounts. Neither changes last year's filed accounts or any CT600.
How do I claim a balancing allowance when my company stops trading?
Enter the prepared main or special rate pool balancing allowance under Tax adjustments. Check box 705 or 695 and the separate computation line in the draft before filing.
Balancing allowance on cessation of trade: how it works for a limited company →
Is the micro-entity turnover limit reduced for short accounts?
Yes. The turnover ceiling is adjusted for the accounts-period length. Under the limits applying from 6 April 2025, a six-month period has a £500,000 ceiling. Asset and employee limits are not proportionately reduced. The full qualification rules still apply.
Do I lose micro-entity status after one year above the limits?
Not necessarily. In later years a change in meeting the size conditions affects qualification only after two consecutive years. The first financial year has its own rule, and exclusions and the April 2025 transition also matter. A current-year comparison alone does not decide qualification.
Can I add a going concern note to FRS 105 micro-entity accounts?
Yes. On the Financial data step, expand Optional notes to the accounts, then tick Include a going concern note and type the wording, for example that the directors have received confirmation of continued financial support from the shareholders. It prints as a numbered note after Average number of employees in both the HMRC and Companies House copies. FRS 105 requires the directors to assess going concern but does not require a note, so leave the box unticked if you do not want one.
Do micro-entity accounts need an off balance sheet disclosure note?
Only where the company is party to arrangements not reflected in its balance sheet and their risks or benefits are material (Companies Act 2006 section 410A). A nil statement is not required, but many accountant-prepared accounts include one. In Optional notes to the accounts on the Financial data step, choose No to print the line Off balance sheet disclosure, No, choose Custom to print your own wording, or leave it as Not included. Your chosen wording appears in both copies of accounts we generate. Unincorporated clubs use customer-prepared accounts, so add any notes to that file before uploading it.
Where do I put individual disposal calculations for my company?
Paste them into Disposal calculations under Tax adjustments. HMRC requires individual workings, including relevant claims or elections, when boxes 210, 215 or 825 are completed. We attach your text without recalculating it. There is one field per return. You can continue with it blank, but a return requiring the workings is incomplete without them.
Are current creditors the same as trade payables?
No. Current creditors can include suppliers, tax and director loans due within one year. Enter the aggregate once. We tag it as current creditors without requiring a supplier breakdown.
What does Net assets (liabilities) mean on my balance sheet?
It is total assets less all liabilities, equal to capital and reserves. Brackets show net liabilities: liabilities exceed assets. For example, assets of £2,000 less liabilities of £5,000 appear as (3,000). The wizard, import previews, review and generated accounts use the same caption for positive, zero and negative figures. It does not change your figures or automatically add a note.
Why ask whether a dormant company has traded before?
Dormant this year and never traded are different accounts classifications. For a new dormant draft we use your answer to select the right classification, without evidence checks. We do not ask when its first period starts on incorporation. Existing drafts keep their saved behaviour.
Does the first-year allowance breakdown give another tax deduction?
No. It explains the first-year amount already included in total capital allowances. A £3,500 total including £500 of first-year allowance still gives a £3,500 deduction, not £4,000.
Director's loan waivers
When can a company use the corporate rescue exemption for a debt release?
CTA 2009 section 322(5B) has conditions about the type of release and a material risk that the company would be unable to pay its debts within the next 12 months without the release and related arrangements. Read the full conditions before choosing a treatment.
Company in financial difficulty: debt releases and the corporate rescue exemption →
Is a director’s loan waiver taxable for the company?
A director loan release can create a profit and loss credit. The company may bring it into account as a trading or non-trading loan relationship credit, or a statutory exception may apply. The company chooses the treatment for its filing.
Director writes off a loan to their company: is the release taxable for Corporation Tax? →
Where do I enter a full or partial director loan write-off?
In Step 2, open Tax adjustments and add a director’s loan waiver. This is for money the company owed the director that the director legally releases. The accounts note’s “Written off during this period” and “Waived during this period” fields are the reverse: amounts a director owed the company. Enter the amount legally released, effective date and tax treatment. Enter the balance still owed in Creditors: due within one year or Creditors: due after more than one year, splitting it if necessary. We generate the accounts and Corporation Tax return automatically, including two returns for a long accounting period. The whole release must be recognised as a profit and loss gain. Choose the tax treatment, including a statutory exception if it applies. A release credited wholly or partly to equity needs a different calculation that this form does not offer.
Do I need a prior-year director’s loan waiver amount when this year has the first waiver?
No. When you add a current-year waiver in Tax adjustments, the Prior-year director’s loan waiver gain (if any) field appears beside it when a prior year applies. Enter the prior year’s total gain if there was one. Leave it blank if there was no earlier waiver.
Does a director’s loan waiver go in Other income or CT600 box 205?
No. Enter it once using Director’s loan waiver under Tax adjustments, not Other income. A trading amount is included in boxes 155 and 165. A non-trading amount enters the loan relationship calculation, whose net profit may appear in box 170. A statutory exception credit stays in the accounts but is removed from the taxable result. Box 205 is only for income not included under another CT600 heading, so using it would count the waiver twice.
Will I see a director’s loan waiver amount on the CT600 PDF?
No. The CT600 PDF has no separate waiver amount box. A taxable trading credit affects the totals in boxes 155 and 165. A taxable non-trading credit enters the combined loan relationship calculation, whose net profit may appear in box 170. For a statutory exception, the gain stays in the accounts and the tax computation PDF names both the gain and its deduction. The CT600 shows the resulting taxable totals, without a separate excluded waiver amount in boxes 155, 170 or 205.
Where can I find official guidance on director loan waivers and the CT600?
For a loan owed by the company to its director, read these official HMRC sources. They are useful whichever filing software you use.
Capital losses, dividends and AIA
What allowance does the automatic capital loss calculation assume?
When no company allowance is stated, it assumes the maximum for the period. This is not a check of your entitlement. Use your own calculated relief if your allowance is lower, even below £5 million.
Can I use a manual capital claim with other restricted losses?
Not every mixed-loss case is supported. If other brought-forward relief is used and the shared allowance restriction applies, the return can still be blocked because the service does not collect a restricted deduction for every other stream. Your manual capital claim does not override that limitation.
What is a brought-forward capital loss?
Can capital losses reduce trading profit?
Is the opening capital loss balance the amount I can deduct?
When does the brought-forward capital loss restriction apply?
Does every company have a £5 million capital loss allowance?
Can I file using my own calculated capital loss relief?
What happens to unused capital losses?
How do I enter capital losses when filing two CT600 returns?
What if I do not know my brought-forward capital loss balance?
Does a blank capital loss relief entry mean zero?
Can a six-month AIA claim use a monthly calculation?
Are all UK dividends received by a company exempt?
Can I deduct foreign tax credits from the taxable dividend field?
Non-trading loan relationship deficits
Is a foreign exchange gain taxable for a limited company and which box does it go in?
A taxable non-trading exchange gain is included with other non-trading loan relationship credits and can contribute to CT600 box 170. The treatment depends on why the balance is held.
Foreign exchange gains and losses and Corporation Tax for a limited company →
Where do I enter a foreign exchange loss on the CT600?
A non-trading exchange loss included in Other charges can be entered as a loan relationship debit. It contributes to CT600 box 795 after non-trading credits are netted.
Exchange losses on a CT600: where a foreign exchange loss goes (box 795) →
Where do I input my Brought Forward Non-trading Loan Relationship Deficit?
Open Step 2 of your filing, go to Tax adjustments and enter the unused qualifying balance in “Non-trading loan relationship deficits brought forward”. Review the claim directly underneath it. Do not put it in trading losses brought forward or add it to this year’s interest expense.
What is a non-trading loan relationship deficit?
It is a tax loss arising when allowable non-trading loan relationship debits exceed taxable non-trading loan relationship credits. It is separate from a trading or property loss and is not the outstanding loan balance. Non-trading mortgage interest in a property company is one possible source.
Can I choose how much brought-forward non-trading deficit to claim?
Yes, for the eligible total-profits claims this feature supports. Leave the claim blank to use the calculated maximum, enter a smaller amount to claim less, or enter 0 to make no claim on that return. The opening balance is not itself the claim. Review the deductions allowance as well.
How do I enter a brought-forward loan deficit for accounts longer than 12 months?
Enter the opening balance once. The inline splitter below the field shows the two Corporation Tax returns, with a separate claim and deductions allowance for each. The first return’s unused balance carries into the second. The balance is not day-apportioned and the two claims do not have to use it all.
Why is my maximum claim £0 when a balance remains?
Your non-trading deficit balance is what remains available, not what you can necessarily use on this return. In a completed calculation, a £0 maximum with a positive balance means there are no profits left against which to claim that brought-forward deficit after other reliefs. The unused eligible balance carries forward. For example, Return 2 can show £90,000 available but a £0 maximum claim. Check the calculation and resolve any validation messages before relying on the figure.
What happens if I claim zero in both returns?
Entering 0 in both non-trading deficit claim fields means neither return uses your brought-forward balance. If you start with £90,000, that existing balance remains £90,000 to carry forward beyond Return 2, assuming no other changes to it. Neither return receives a tax reduction from that balance. Future use remains subject to eligibility and available profits. Enter an explicit 0 in each claim field because leaving a field blank uses our calculated maximum instead.
Which CT600 box is used for a brought-forward non-trading loan deficit?
Box 263 records an eligible brought-forward deficit claimed against total profits. Box 260 is for current-period deficit relief, while box 795 reports the deficit arising in the return. Restricted brought-forward deficits using box 230 are not supported by this feature.
Getting started
Can I get help setting up a CT600 or Companies House filing?
Yes. Open Need help setting up your filing? below What are you filing? The helper explains HMRC CT600 returns, meaning Corporation Tax returns, and Companies House accounts separately. Each question has a help icon. If the first CT600 has never been filed and the second is already filed elsewhere, choose The first HMRC CT600 return, with the second already filed. The first goes as new and the second is sent again as an amendment even if unchanged. This route is HMRC only. Select the full accounts dates, using Enter custom accounts dates if the period is missing. Missing suggestions do not by themselves mean different HMRC dates. For a long first year, each HMRC return is shorter than the accounts period. You can check or enter the HMRC dates and the helper uses the regular long-period route if the returns together cover the full accounts period. When the HMRC coverage genuinely differs in Enter my figures once mode, it proposes HMRC only and tells you to file any outstanding Companies House accounts separately. An already-separate draft can keep both destinations for a supported date combination. Review the proposed destinations before selecting Apply settings. Use the help icon beside Proposed settings for an explanation of that outcome, what is and is not included, and links to the relevant filing guide, knowledge article and official guidance. When settings are applied to your current draft, the questions are replaced by a Filing settings applied summary showing the destination and accounts and HMRC CT600 dates. The summary is brought into view. Nothing has been submitted. Review the settings below, then select Save Progress or Next to save them to your account. You can also continue using the existing controls. If you switch from separate figures to the remaining CT600 route, accept the warning to clear those separate entries, then enter the remaining return figures in the normal financial fields. Your statutory accounts figures and shared loans are kept. If you change a correction to new returns through the helper, it saves the correction separately and keeps your current figures, allocations and trading status in a new filing in this tab. If saving fails, the correction remains open. Starting a filed-elsewhere correction keeps your selected trading status.
Can I file my first CT600 if only the second return is already filed?
Yes. For accounts over 12 and no more than 18 months, choose Amend filing made elsewhere, HMRC CT600, then File the first CT600 as new and amend the second. Review both returns. The first is new and the second is an amendment. Full accounts accompany each return that overlaps the accounts period. A return wholly after the accounts end carries the existing accounts-omission explanation instead. The second is sent again as an amendment even if its figures have not changed. Both returns tick box 50 so HMRC knows they are being made together.
Why isn't my Net Assets or Total row imported?
Calculated lines such as Net Assets and Net Current Assets are left out so they do not add to the account balances. A Total for row can supply a summary when its section has no account detail. Totals that repeat imported accounts are skipped. Open Headings, totals and percentage rows to inspect them. Use this total only when the detailed rows are missing, then check the resulting figures before applying.
Can I import last year's figures for the comparatives?
Yes. Select Prior year amount for a two-year report, or choose Import into: Prior year for a separate last-year file. Supplied lines replace the comparatives. Missing lines keep their values. First-period filings hide these controls.
Can I import a Sage profit and loss with no sales?
Yes. A standard single-amount Sage profit and loss export with expense account rows, an empty Sales section and Total Sales £0.00 supplies Turnover £0. If your draft already holds turnover, Review changes lets you keep it or replace it. Missing lines keep existing figures. Check all figures after import, especially in customisable or comparative-column reports where empty section totals do not automatically supply zero.
Why does my import say rows have the opposite sign?
A filing line may total below zero, or a split amount may have the opposite sign to its account. Pence are preserved, so even a small negative total can need correcting. Move the account to the right line, mark it Not used, or correct the split. Check the resulting totals before applying.
Can I import my Sage Accounting reports?
Yes. Export prepared reports as CSV. In Financial data select Import profit and loss or Import balance sheet in the relevant section header. Choose Sage Accounting, select Continue, upload the file and review the mappings. For long periods, allocate relevant amounts between both returns.
How does a trial balance map to micro-entity accounts?
Each ledger account is grouped into a statutory profit and loss or balance sheet heading. You must review ambiguous accounts, signs and retained earnings before using the totals.
Can I import my own Excel or CSV accounts spreadsheet?
Yes. You can use your own Excel workbook without Xero or QuickBooks. Put prepared account names and amounts on separate profit and loss and balance sheet sheets, save as XLSX or CSV, and select Import profit and loss or Import balance sheet in Financial data. Choose Another spreadsheet or CSV and select Continue. Codes and types are optional. For monthly reports, select the full-period total, not every month plus the total. The linked guide has a realistic 49-account Excel example, matching CSV files and exact column settings. Review the mappings before applying the figures. With only a few totals, manual entry may be quicker.
Can I import a trial balance with opening, movement and closing balance columns?
Yes. A complete closing debit and credit pair is proposed, including CBDEBIT and CBCREDIT or Closing Dr and Closing Cr. A single closing column is not mixed with ordinary Debit or Credit. Check the proposed columns and change them if needed before reviewing the mappings.
Why does the import say my Grand total does not match?
The Grand total differs from the sum of the monthly columns by more than one penny and no other amount column is selected. Check the spreadsheet totals, then import a corrected file or choose the full-period amount column yourself. Choosing a column removes the warning. Comparisons, budgets or unreadable amounts prevent a Grand total proposal, but an ordinary Total, Amount, Balance or Net column can still be proposed.
My profit and loss shows income and costs as negative numbers. Can I import it?
Yes. How signs are shown includes Income and costs are negative. It is proposed for a profit and loss with at least two non-zero account amounts when all are negative. The file cells retain their signs while reviewed income and costs use the chosen convention. Check the setting and mapped totals before applying. Your explicit sign choice stays when you change columns or the heading row.
Can I import a profit and loss CSV without column headings?
Yes. Use No heading row (data starts on row 1), then choose the columns containing account names and amounts. Codes are optional and section names can vary. Select Profit and loss and check How signs are shown. A column containing only calculated totals is not an account amount column. If several amount columns could apply, choose the full-period column. Review the first account and mapped totals before applying. You do not need a year heading.
How do I export a trial balance from QuickBooks?
Open Reports in QuickBooks Online, run the Trial Balance for the accounting period you are filing and choose Export to Excel before importing it into #Simple CompanyTax.
How to export a trial balance, profit and loss or balance sheet from QuickBooks →
How do I export a trial balance from Xero?
Open Accounting reports in Xero, run the Trial Balance for the accounting period you are filing and export it as CSV or Excel before importing it into #Simple CompanyTax.
How to export a trial balance, profit and loss or balance sheet from Xero →
Why does an imported account need confirming?
The review shows all account mappings, with accounts needing confirmation highlighted in amber. Recognised bank overdrafts and VAT recoverable balances are placed automatically and remain editable. The file can identify an account without settling which filing line it belongs to. We propose a line and explain the doubt. Confirm it or select the line to explore descriptions and alternatives. Assign saves your choice and keeps the account amber until you confirm it. Apply change assigns and confirms your choice immediately. Cancel leaves it unchanged, and Undo reverses the latest mapping change. Confirm all accepts every proposal shown.
What do Heading row, Account type and Amount layout mean when importing a spreadsheet?
At Which row has your column names?, choose the heading row or My file has no heading row. Use the dropdown above each column to choose Account name, optional Account code and Account type, and either Amount or both Debit and Credit. Prior year amount is available for a comparative column when importing into this year. Changing a grid column’s role replaces its previous role. The labelled controls under Columns use the same selections and include help icons. Changing Report type keeps your chosen Amount column. Recheck How signs are shown and the totals, then select Review mapping.
Can I import a Xero, QuickBooks or Sage export I have edited?
Yes. Choose its software under Where are your figures from? on every import. A recognised unedited export opens Review directly. An edited export opens the heading and columns grid so you can confirm the row and column roles. Choose one Amount column or both Debit and Credit, check the period and review every mapping. If a file clearly matches a different supported vendor template, Exported from shows that vendor and can be changed.
Can I import a bank statement?
No. Bank statements and transaction lists do not contain prepared account balances. Import a trial balance, profit and loss report or balance sheet in CSV or Excel instead. Keep one report per sheet. If a workbook contains a transaction sheet and a financial report, choose the financial report under Workbook sheet.
Do imported figures keep pounds and pence?
Yes. We add all confirmed accounts mapped to each statutory line in pence and preserve that total in the profit and loss and balance sheet. Each statutory profit and loss category is rounded once for Corporation Tax. Compare the resulting figures with your report before applying them.
Is my trial balance file stored?
Your original CSV or Excel file stays in your browser and is not uploaded or stored. The figures you apply and your mapping choices are saved with the draft. Separately, private import diagnostics retain parsed sheets, account names, codes, amounts, mapping changes and errors for up to 180 days so we can investigate problems. These details are not anonymised or sent to advertising providers. Keep the original file with your records.
Can I import a trial balance from Xero or QuickBooks?
Yes. In Financial data, select Import profit and loss or Import balance sheet in the relevant section header to import a Xero or QuickBooks trial balance, profit and loss or balance sheet in CSV or Excel format for your CT600 and annual accounts filing. You can import current-period figures and prior-year comparatives. Review the period, every suggested line and the figures you choose to apply. Both buttons open the application choices first. How to import your data is in the import window header. It opens the import steps in a new tab while your filing stays open.
Can I import prior-year figures for my accounts comparatives?
Yes. You can import prepared prior-year financial-report figures for the comparative column in your annual accounts. Review the period, mappings and any differences from prior-year figures already in your draft before applying them. Keep current-period and prior-year amounts separate, then check both columns in the accounts preview.
Can I import a profit and loss and balance sheet separately?
Yes. Select Import profit and loss beside the status pill in the Profit & loss section header, import the report and apply its figures. Then select Import balance sheet in the Balance sheet section header, beside its status pill, and choose your balance sheet file. Both reports stay recorded in the same draft and the second import does not clear the first.
Do I need to connect my Xero or QuickBooks account to import data?
No. #Simple CompanyTax uses file imports. Export your trial balance, profit and loss or balance sheet from Xero or QuickBooks, then select Import profit and loss or Import balance sheet in Financial data. You do not connect your accounting account or share its password. Review the mappings before applying the figures.
Why will my trial balance CSV or Excel file not import?
Use a CSV, TXT, XLS or XLSX report of account balances, within 1 MB and 2,000 rows per sheet. PDFs and bank transaction lists are not the report formats this importer is designed for. Export a fresh report if the file cannot be read. For a layout that is not recognised, choose the report type and columns. For unreadable formula cells, export their values.
What happens when I import an updated trial balance?
The importer compares each filing line with the earlier import. It selects Keep current when you changed a figure afterwards, and proposes Clear for unchanged previously imported lines missing from the new file. Review changes lets you choose Keep current, Replace or Clear.
Can I import figures for an accounting period longer than 12 months?
Yes. Import the figures for the full accounts period. If amounts still need allocating between your two Corporation Tax returns, the import message lists them all. Select Allocate beside each amount to open its controls and choose how much belongs to each return using the dates shown. The list updates as you finish. Valid existing allocations stay unchanged.
Why does Review filing say my tax figures are still being recalculated?
Review filing waits for the latest tax calculation after an edit. If you see “Period end must be after period start”, “An accounting period longer than 18 months is not supported. Check the dates and enter a period of 18 months or less.”, “The period end date is before the start date. Check the dates.” or “This period is longer than 24 months, so it cannot be filed as two Corporation Tax returns. Check the dates.”, check Period start and Period end on Company & period and correct any mistyped date. Keep the real dates, your figures and allocations between both CT600 returns. Do not shorten a genuine period or start a new blank filing to remove the message. If "Your tax figures are still being recalculated for the latest changes. Give it a moment and try again." stays on screen, select Save Progress, check for Saved to your account, reload the page and try Review filing after the calculation finishes. Your saved figures and allocations between two CT600 returns remain available. The free preview needs no subscription. An active subscription is needed only to submit. If the message persists after reloading, contact support with the message and your company number.
I selected New filing and my saved figures are not there. Are they lost?
No. New filing always opens a blank form, even when the company has saved progress. A notice at the top names the saved accounting period and when it was last saved. Select Resume saved filing in that notice before saving anything. Selecting Save Progress, Next or Back on the blank form replaces the company's unfinished new-filing progress. Saved amendments and filed returns are kept separately.
Does importing a trial balance or spreadsheet change my accounting period or CT600 dates?
No. The import fills only the Financial Data figures you approve with Use these figures. It never changes the accounting period, the CT600 split date or your other answers on Company Profile & Period. Choose a report column that covers your whole accounts period. For a period longer than 12 months, import one full-period report and then allocate any listed amounts between the two returns.
My spreadsheet has monthly columns and a year-to-date total. Which one do I import?
Choose one column that covers the whole accounts period, usually the year-to-date or Grand total column, and set the monthly columns to Not used. Adding the months and the total together counts the money twice. For an accounts period longer than 12 months, the total must cover every month of it. Importing a column never changes your filing dates.
Why is my filing blank when I come back?
Add the company first, then select Save Progress, Next or Back and check for Saved to your account. Before a company is added, figures are kept only in that browser tab. New filing starts with blank dates and figures. Resume saved filing reopens the saved copy. The notice identifies its accounting period and last saved UK date and time. Incomplete dates show Period not completed. Saving a new form replaces unfinished new-filing progress for that company.
Can I file a CT600 as a property management company (box 4 code 7)?
Yes, for an active company. Choose the ordinary company route. On Financial data, open Profit & loss and select Property management company under Company tax type immediately above Corporation tax. In separate-figures mode, choose on the CT600 1 tab. The CT600 2 tab shows the same choice, locked. This type applies to both returns. Selecting a type replaces the previous choice for the whole filing. This service cannot file returns whose company type differs between them. Hover over an option or focus it with the keyboard for help. Select Standard company to withdraw the choice. The dormant journey does not offer code 7.
Do I need to prepare my own figures?
Yes. You provide the financial figures and choose the tax treatments. We prepare the filing documents from your entries. Take advice if you need help preparing your figures.
Can I preview my filing before I pay?
Yes. Start your free preview without entering card details and review your draft filing documents before subscribing. An active subscription is needed to submit.
Do I need an accountant to file my company tax?
Not necessarily. A director can file a straightforward micro-entity CT600 and accounts using suitable software. Use an accountant if the company has complex transactions, group relief, R&D claims or anything outside our supported scope, or if you are not confident about the tax treatment. Associated companies are fine: you enter how many and we divide the Corporation Tax limits for you.
What is "company tax" in the UK?
When people say "company tax," they usually mean corporation tax, the tax UK limited companies pay on their profits. Your company files a corporation tax return (CT600) to HMRC after each accounting period, reporting its income, expenses, and the tax owed. Corporation tax is charged at 19–25% depending on the profit level.
What is a CT600?
A CT600 is the Company Tax Return used to report a company's taxable profit or loss and Corporation Tax to HMRC. Most returns are filed online with iXBRL accounts and a tax computation. A company must file when HMRC issues a notice to deliver a return, even if it made a loss or owes no tax. A company HMRC has confirmed as dormant usually does not file again unless HMRC sends another notice.
What if my company made no money?
You still need annual accounts for Companies House, and you must file a Company Tax Return if HMRC has sent a notice to deliver one. No taxable profit normally means no Corporation Tax, but the filing deadlines still apply. If the company is genuinely dormant, tell HMRC so it does not keep requesting returns.
What is the difference between a CT600, annual accounts and a confirmation statement?
They are separate filings. The CT600 reports Corporation Tax to HMRC. Annual accounts go to Companies House. A confirmation statement updates the company details Companies House holds. SimpleCompanyTax files the CT600 and annual accounts, but not confirmation statements.
What if my company is dormant?
Dormant companies still file annual accounts and a confirmation statement with Companies House. If HMRC has issued a notice to deliver a Company Tax Return for the period, file that return and tell HMRC the company is dormant. HMRC normally stops requesting later returns until the company becomes active again.
HMRC asked me to file a return where the start and end date are the same day. Is that right?
Yes. A one-day "stub" return can arise when a company is incorporated on the last day of a month, because HMRC limits a Corporation Tax period to 12 months. Enter the same date in both period fields. The stub goes to HMRC only and does not replace the longer Companies House accounts period.
Do my annual accounts and my Corporation Tax return have to cover the same dates?
Usually they do, but not always. If your company was dormant and then started trading, your annual accounts can cover the whole period while HMRC expects a shorter Corporation Tax return from the trading start date. That works for a first year running from incorporation and for a later year in which the company was dormant at the start. Check your HMRC business tax account and CT603 notice before filing because HMRC may ask for a dormant-period return as well. Where HMRC expects the shorter period, we attach the full accounts and select CT600 box 85.
Pricing & payment
How much does SimpleCompanyTax cost?
Two simple prices, per company, per year: £10 +VAT for dormant companies (no trading activity in the period) and £25 +VAT for trading micro-entities (FRS 105). Personal pricing cards show +VAT when tax is added at checkout. Each subscription covers one year. UK VAT illustrations: UK VAT illustration: £10.00 + £2.00 VAT (£12 total) for dormant companies and UK VAT illustration: £25.00 + £5.00 VAT (£30 total) for micro-entities. New Practice purchases exclude VAT. Existing Practice subscriptions keep their current VAT-inclusive renewal price. Both tiers include CT600 generation, iXBRL accounts, direct HMRC and Companies House filing, unlimited filings and amendments for that company during the annual subscription, and downloadable documents. No hidden fees, no per-filing charges and no premium add-ons.
Does one annual subscription cover multiple filings and accounting periods?
Yes. One annual subscription covers unlimited filings, amendments and accounting periods for the same company, per year. There is no extra fee for another supported accounting period or for correcting and re-filing that company. A different company needs its own subscription, unless you use a Practice plan that includes multiple company slots.
Why do you charge two different prices?
Dormant filings and trading micro-entity filings are genuinely different pieces of work: a dormant return has no P&L, no tax computation, no fiscal-year apportionment, and a smaller set of iXBRL tags. Pricing each tier accordingly is fairer (and cheaper for dormant filers) than averaging them into one number.
How can you charge only £10 +VAT for dormant filings?
Our focused scope lets us automate 99% of the computation and filing logic for dormant companies and micro-entities. We don't employ accountants to manually review every return, because the software handles validation and compliance checking automatically. By serving two well-defined markets, we build deep automation and pass the savings on.
What if my company was dormant last year and is trading this year?
No problem. You pick the plan that matches this filing year at checkout. Next year you pick again. We don't lock you into a tier.
What payment methods are accepted?
We accept all major credit and debit cards (Visa, Mastercard, Amex) via Stripe. All payments are processed in GBP. We never see or store your card details, because Stripe handles all payment security.
Can I get a refund?
If you're not satisfied with the service, contact support and we'll work with you to resolve the issue.
How do I cancel my annual subscription or stop it renewing?
Sign in, select Manage billing in the top navigation, then cancel the subscription in the secure Stripe billing portal. Cancelling stops the next annual payment. You keep access until the end of the period you have already paid for. If you cannot open the billing portal, contact support with the company name and company number. Never send card details by email.
What happens when I use all my Practice slots?
You can choose more than one of the same Practice plan at checkout. Those units renew and cancel together. For example, two units of Practice 10 give you 20 company filing slots. You can add another plan later from your Team page. That new subscription has its own renewal date and slots. Cancelling renewal keeps your plan available until the end of the year you have paid for.
Eligibility & scope
Do I need to amend last year's CT600 to carry a trading loss back?
Make the claim in the return for the period that made the loss, or an amendment to that loss-period return. Enter your calculated carry-back amount. The computation states the claim and box 45 is ticked. HMRC gives effect to it in the earlier period. This service does not amend the earlier receiving return.
Does ticking CT600 box 45 make a loss carry-back claim?
Ticking box 45 only marks that a claim affects an earlier period. Enter the calculated amount in Trading loss carried back to include the claim statement and reduce losses carried forward. A positive amount ticks box 45 automatically.
What does Special tax regimes mean in the filing wizard?
Special tax regimes on the first step decides which return is built. No keeps the ordinary company filing to HMRC, Companies House or both, with a tax computation for an active company. Charity claiming full exemption and Community amateur sports club (CASC) claiming full exemption file a CT600 with CT600E to HMRC only, claiming all income and gains exempt, with no tax computation and nothing filed at Companies House. They cannot claim partial exemption. A period over 12 months files two CT600s, each with its own CT600E.
Does a CIO need a Companies House number to file a Company Tax Return?
No. A charitable incorporated organisation is registered with the Charity Commission, not Companies House. Use its Corporation Tax UTR in CT600 box 3 and its charity number in CT600E box E10 if applicable. Do not enter the charity number as a company registration number.
What do I enter in box E10 for a CIO or SCIO?
Enter the Charity Commission registration number for a CIO or the OSCR number for a SCIO, such as SC012345, if applicable. E10 is separate from the Corporation Tax UTR in CT600 box 3 and the HMRC repayment reference in E5. The field is optional and customer-entered.
SCIO Corporation Tax return: what an OSCR-registered charity sends to HMRC →
Can a CIO send its accounts to HMRC as a PDF?
Yes. HMRC Chapter 6 paragraph 6.9.7 permits PDF or iXBRL accounts from incorporated charities not required to prepare accounts under the Companies Act or Friendly and Industrial and Provident Societies Act 1968, including CIOs and SCIOs. This permission has no income threshold. The smaller Companies Act charity concession is a separate rule.
CIO or charitable company: how Corporation Tax filing differs →
Can a CIO or SCIO file a CT600E with you?
Yes. Wholly exempt CIOs and SCIOs use Not registered at Companies House, then Charity claiming full exemption. This files CT600 and CT600E with HMRC only, including both returns for periods over 12 months and up to 18 months. Supply your PDF or iXBRL accounts, or your explanation for omission. Partly taxable charities, trusts and trading subsidiaries are outside this route.
Who signs the Company Tax Return for a CIO?
The proper officer of a CIO or SCIO is normally the secretary or acting secretary, or the treasurer if there is none. Another authorised person can act except where a liquidator has been appointed. A liquidator or administrator is the proper officer when appointed. Enter the actual capacity in Status. Use the details of the person authorised to sign.
Can a partly taxable unincorporated charity use this route?
No. The charity association route supports full exemption on all income and gains for every CT600 period. Do not choose full exemption for a partly taxable charity. Registered CASCs retain their separate full, partial and no-claim treatments.
Can an unincorporated charity file a CT600E return?
A charitable association can file CT600 with CT600E using its Corporation Tax UTR. This service supports full exemption, periods up to 18 months and supplied PDF or iXBRL accounts, or a reason for omitting accounts. Partly taxable charities and charitable trusts are outside this route.
Can a PTA file a CT600 without a company number?
An unincorporated charitable PTA can file a wholly exempt CT600 and CT600E using its Corporation Tax UTR, without a Companies House number. A charitable trust uses Self Assessment instead.
What types of companies does SimpleCompanyTax support?
#Simple CompanyTax supports eligible UK private micro-entity companies limited by shares or guarantee, including trading, dormant, property, associated companies and CICs. Separate HMRC-only routes support wholly exempt charities, including CIOs, SCIOs and charitable PTAs, CASCs and unincorporated clubs, including golf clubs. Charity and club routes use customer-prepared accounts. We do not support LLPs, PLCs, sole traders, partnerships, group accounts or partly taxable charities.
Can I file for a company limited by guarantee?
Yes. We file the CT600 and FRS 105 micro-entity accounts for a UK private company limited by guarantee, trading or dormant, to HMRC and Companies House together or to either one. We read the legal form from the Companies House record when you add the company, so there is nothing to select, and both Companies House forms are accepted, with or without Limited in the name. Being limited by guarantee does not by itself change the ordinary Corporation Tax calculation, which still depends on the company’s own activities, income and claims. The exception is a charitable company, which cannot use micro-entity accounts and needs the CT600E page.
Can I file for a community interest company (CIC)?
Yes. #Simple CompanyTax supports eligible micro-entity CICs limited by shares or by guarantee. We file your CT600, tax computation and accounts with HMRC. Choose Simplified or Detailed in the CIC34 report card on Financial Data and complete the questions to prepare your Companies House ZIP package, containing your accounts and CIC34 report. You download and upload it yourself through the Companies House CIC accounts service, which charges a separate £15 fee. Leave the report selector on None if you only want the CT600 filing route.
Can I get my CIC's Companies House package before filing the CT600?
Yes. Choose Companies House on Company Profile & Period, complete a Simplified or Detailed CIC34 report on Financial Data, and review your figures. Select Continue to Generate Package. In the window, leave HMRC unticked and enter the director who approved the accounts and the approval date. These start empty. Select Generate Companies House CIC Package. No CT600 declaration is needed to generate the package. An active subscription is required. Download the ZIP from your filing page and submit it yourself through the Companies House CIC accounts service for its separate £15 fee. No UTR or Government Gateway details are needed to build the package. If your CT600 is still due, you can file it with HMRC only from the same filing. Long accounts periods produce one ZIP, and a CT600 filing from the same filing produces two CT600s using the saved figures and allocations. This route is for original CIC accounts, not amendments, one-day accounts engagements or a remaining CT600 without accounts. Different accounts and CT600 periods require separate figures to generate the package. A short second CT600 within long accounts does not prevent the full-period ZIP.
Why is there no Companies House package on my CIC filing page?
The CIC34 report card on Financial Data starts on None. With None, #Simple CompanyTax files the CT600 with HMRC only and builds no package. Choose Simplified or Detailed and answer every required question before you review the filing. The download appears on the filing page after you submit, not on a preview. No package is built when you file only the remaining CT600, because the accounts went with the first return.
Why can’t SimpleCompanyTax send my CIC’s accounts to Companies House?
Because Companies House does not take a CIC’s accounts directly from filing software. Its filing rule 2422 rejects a community interest company’s accounts sent through the software gateway, whichever software sends them. Since April 2025 a CIC files package accounts instead: software prepares a ZIP containing the accounts and the CIC34 report, and the company itself submits it through the Companies House CIC accounts service at find-and-update.company-information.service.gov.uk, signed in with its authentication code. We build that ZIP for you and file the CT600 to HMRC. We never claim to have filed with Companies House for a CIC.
What is in the Companies House package for my CIC and how do I submit it?
The ZIP contains your accounts and CIC34 report. On the review page, choose the publication option in Your Companies House package and generate the documents. After filing, download the ZIP from Your Companies House package on the filing page, which also has an Open Companies House button. Sign in to the Companies House CIC accounts service, choose package accounts and upload the ZIP unchanged, then submit it. Pay the separate Companies House charge and keep its receipt. The linked guide shows each screen. HMRC filing is a separate outcome.
How much does Companies House charge a CIC to file its accounts and CIC34 report?
Companies House charges a £15 fee when the company uploads its CIC report and accounts through the CIC accounts service, paid by debit or credit card at the time of upload. The fee is paid to Companies House, not to us, and it is separate from your SimpleCompanyTax subscription, which covers the CT600 filing to HMRC and building the package.
Should my CIC file the simplified or the detailed CIC34 report?
Choose the report your directors intend to sign. The detailed report applies if performance-related interest was payable on an outstanding debt or debenture during the year, whether paid or not. It also applies to a CIC limited by shares that declared or proposed a dividend for this year, or declared one in the previous four financial years. Check the complete conditions in the guide. The Detailed choice adds Parts 5 and 6. You determine the report type.
Can a dormant CIC file with SimpleCompanyTax?
Yes. A dormant CIC files a nil CT600 to HMRC in the same way as any other dormant company. It still owes Companies House its dormant accounts and a CIC34 report for the year, so the CIC34 section is shown for a dormant CIC too and the package we build contains the dormant accounts and your report.
Where does a not-for-profit company enter donations and raffle income?
For the ordinary company route, enter donations classified outside trading receipts through + Add other income, under Income not falling under any other heading. Enter the part your company treats as not chargeable in Other income not taxable under Tax adjustments. The accounts keep the gross receipt. Enter raffle trading receipts as gross Turnover and include platform fees in the appropriate expense total, keeping any pence. Add back only costs you treat as non-deductible in Disallowable expenses. Non-profit status does not automatically exempt the income. For accounts longer than 12 months, enter full-period totals and review both CT600s.
Can I use Trading when a not-for-profit company runs a raffle or lottery?
HMRC treats promoting a lottery as trading. A not-for-profit label alone does not exempt the receipts. For the supported ordinary company route, use Trading to enter prepared raffle trading receipts as gross Turnover and fees in the applicable expense row. The company determines the accounting and tax treatment, including whether any concession applies. No separate raffle wizard is needed.
Where can I find step-by-step instructions for the filing wizard?
Start with the company filing walkthrough, which covers setup, Financial data, preview, submission and receipts. Each financial guide has a direct link to its entry details. Field maps show the exact rows and distinguish total amounts, subsets and tax adjustments. Use the guide for your organisation if you are filing for a club, charity, CASC or CIC.
Does a company limited by guarantee have share capital?
No. A company limited by guarantee has members who guarantee a small amount if the company is wound up, usually £1 each, and it has no shares. The wizard does not show the share capital rows for it. Capital and reserves are the retained earnings the company has built up, shown as members’ funds, and that total must equal net assets. The guarantee amount is not entered anywhere: it is not an asset, a liability or capital. If your records use an income and expenditure account, enter each amount by its nature: trading or business income as turnover, rent in the property fields, bank interest in interest received. The surplus or deficit is a cross-check, not a figure you type.
Can a dormant company limited by guarantee file accounts only?
Yes, where dormant accounts are the company’s chosen filing. Select Dormant in setup and Companies House under What are you filing? for accounts only. Enter the prepared balance sheet with members’ funds and no share capital. Do not assume every dormant company has zero balances. A separate HMRC return obligation still needs to be dealt with.
Is a charitable company limited by guarantee supported?
A charitable company cannot use our ordinary micro-entity accounts route. When available, the separate CT600E route supports a private charitable company claiming full exemption, with its own uploaded accounts, for HMRC only.
Are donations divided between both CT600s when a guarantee company’s accounts cover more than 12 months?
Yes, when you enter your figures once. Donations entered under Income not falling under any other heading, and the Other income not taxable adjustment, are divided between the two returns by the number of days in each, because the wizard does not ask for the date of each donation. A one-off donation can therefore appear partly in both returns. If you choose Enter figures separately on the first step, you enter each return’s figures yourself instead. Each CT600 has its own computation.
My flat management company is limited by guarantee. Can I file?
Yes. Residents’ management, right-to-manage and freehold companies can file whether they are limited by shares or by guarantee. Enter only the company’s own figures: ground rent it is entitled to, interest on its own money, its own bank balance and creditors. Qualifying variable service charges and related reserve funds held on statutory trust, subject to the statutory exclusions, are not the company’s income or assets, so keep them out. Active property management companies can declare CT600 box 4 code 7 on Financial data. Many companies are dormant once trust money is excluded and file accounts only when HMRC has not asked for a return. The dormant journey does not offer code 7 yet. Fixed charges are not automatically within that trust rule. We do not decide the lease position for you.
Do you support buy-to-let companies and property SPVs?
Yes, for supported UK micro-entities with UK rental property. Enter gross rental income and costs separately. A property-only company does not need to divide its running costs between businesses. Mortgage interest goes in Interest payable, and unused property losses go in Tax adjustments. You supply the applicable associated-company count.
Where are the audit exemption options?
You will not see separate audit-exemption questions. Supported micro-entity accounts are prepared as audit exempt under section 477, with the related section 476 and micro-entity statements. If the company needs an audit or members have requested one, SimpleCompanyTax is not suitable for that filing.
Do you support companies with associated companies?
Yes. Two companies are associated when one controls the other, or the same person or people control both, for example a director who owns a consultancy and a property company. HMRC divides the £50,000 and £250,000 Corporation Tax limits by the number of associated companies plus one. In the Tax adjustments section you enter the number of other companies associated with yours at any point in the accounting period (box 326, which is 0 for most companies), and we apply the divided limits and the marginal relief. We do not ask about it anywhere else and we do not decide for you whether companies are associated. Companies that carried on no trade or business in the period do not count. A passive holding company is left out under the passive-company exclusion only when it meets every HMRC condition for the whole period, which our associated companies guide lists.
I entered a number of associated companies but box 326 is blank on my CT600. Why?
Because HMRC only asks for box 326 on a return that needs it. Its Company Tax Return guide says you must complete box 326 if the company’s profits are chargeable at the small profits rate, the company is entitled to marginal relief, or the company is large or very large for quarterly instalment payments. On a return with no profits chargeable to Corporation Tax (box 315 nil, for example a loss-making year) none of those apply, so box 326, box 329 and the rate rows in boxes 330 to 395 are all left blank, in the PDF and in the electronic return HMRC receives. Your saved figure is not lost or changed to zero. It is shown on the review page and is filed in box 326 on any return that has taxable profits, with the divided limits applied.
What is an associated company for Corporation Tax?
A company is associated with yours when one controls the other, or when the same person or group of people control both (Corporation Tax Act 2010, sections 18E to 18J). Control usually means more than half the shares, voting rights, income or assets. It counts if it was associated at any time in the accounting period, even for a day. Companies owned by a relative count only where the two businesses are substantially interdependent. Dormant companies with no trade or business do not count. A passive holding company is left out under the passive-company exclusion only when it meets every HMRC condition for the whole period, which our associated companies guide lists.
How do associated companies affect Corporation Tax?
They divide the limits that decide your rate. The £50,000 small profits limit and the £250,000 upper limit are each divided by the number of associated companies plus one, so a company with one associate is tested against £25,000 and £125,000. That can move a company from the 19% small profits rate into marginal relief, or from marginal relief to the 25% main rate. Both limits are divided by the same number, so marginal relief always exists between them. We show the limits we applied on your review page.
Should I use box 326 or boxes 327 and 328?
Box 326 is the number of associated companies for the whole accounting period and is the box almost everyone uses. Boxes 327 and 328 replace it when the period straddles 1 April and either the number changed between the two financial years or the Corporation Tax limits changed between them (as they did on 1 April 2023). Box 327 is the number for the part before 1 April and box 328 for the part from 1 April. Across 1 April 2023 each part is restricted by its own number. For a later 1 April HMRC's calculation applies the higher of the two to the whole period, and we calculate the same way. HMRC accepts box 326 or boxes 327 and 328 together, never all three, so we only offer 327 and 328 when your period straddles 1 April. Leave box 326 at 0 to use them. Once one of 327 or 328 has a figure the other shows a dimmed 0 and files as 0 unless you change it.
What is a large or very large company for quarterly instalments (boxes 630 and 631)?
HMRC treats a company as large when its profits for the period, including dividends received, are more than £1.5 million divided by the number of associated companies plus one, and very large above £20 million on the same basis (for accounting periods beginning on or after 1 April 2019). Large and very large companies pay Corporation Tax in quarterly instalments and tick box 630 or box 631. There are exceptions, for example a first year as large with profits under £10 million, or a tax bill under £10,000. You tick the box yourself in Tax adjustments. We file what you tick.
Does SimpleCompanyTax calculate quarterly instalment payments?
No. We file box 630 or 631 if you tick it, and the previous-period count HMRC asks for from an instalment payer, but we never calculate the instalments, their dates, interest or penalties, and we do not work out whether your company is large. HMRC explains the rules in its guidance on paying Corporation Tax in instalments.
Can I file a return for a period before April 2023 that needs box 625?
Yes. For a return ending on or before 31 March 2023 there are no associated-company boxes (the rate was flat and HMRC does not allow boxes 326 to 328 on those returns). If the company was a quarterly instalment payer and you tick box 630 or 631, we offer box 625, the number of related 51% group companies at the end of the previous period including your own company, and file it as you enter it. Leave it blank if there were none. A period that starts before 1 April 2023 and ends after it files that count in box 326 instead.
Can I claim group relief?
No. Group relief (CT600C), group accounts and consolidation into a parent are outside what we file, and you confirm that when you add a company. Associated companies on their own are fine: you enter the number and we divide the limits. If your company surrenders or claims losses within a group, an accountant is the right route.
What companies are NOT supported?
Currently we don't support: R&D tax credit claims, group relief (CT600C), companies that prepare group accounts or are consolidated into another company's accounts, PLCs, LLPs, and companies with overseas permanent establishments. Companies with associated companies are supported: you enter how many and we divide the marginal relief limits. Short accounting periods are supported, including one-day stub returns, and we reduce the AIA and marginal relief limits for the shorter period automatically.
Can I file for an LLP (limited liability partnership)?
No. We do not support LLP filings. An LLP carrying on a business with a view to profit is normally tax transparent: individual members pay Income Tax on their shares and corporate members pay Corporation Tax on theirs. It normally files an SA800 partnership return and LLP accounts. Exceptions can switch off transparency, so it is not correct to say an LLP can never pay Corporation Tax. Our guide links to the HMRC rules.
Which accounting periods can I file, and how far back can I go?
We support accounting periods starting on or after 1 April 2015, so you can file the current year as well as overdue returns for earlier years. If your accounting period starts before 1 April 2015, SimpleCompanyTax cannot file it. Please note that HMRC's own filing deadlines and late-filing penalties still apply to overdue returns, and HMRC may not accept a very old period online, so check your filing obligations before you start.
Is SimpleCompanyTax recognised by HMRC?
Yes. SimpleCompanyTax submits CT600 returns directly to HMRC via the Government Gateway Transaction Engine and files accounts with Companies House via the CH API. Production filings are accepted today.
My company name is longer than 56 characters. Can I still file?
Yes. HMRC allows 56 characters for the company name on a CT600, while Companies House registers names of up to 160. If your registered name is longer, we shorten it for the CT600 only, abbreviating common words first (Services becomes Svcs) and always keeping the Ltd or Plc ending. The wizard shows you the exact name HMRC will receive. Your accounts, tax computation and Companies House filing keep the full registered name, and HMRC matches the return on your UTR.
Can I use a loss from a previous year to reduce my Corporation Tax?
Yes. Enter an unused earlier trading loss in Trading losses brought forward under Tax adjustments. Same-trade-only losses reduce trading profit through box 160. Eligible post-2017 losses can be claimed against total profits through box 285, including bank interest. Box 160 stays blank in a period with no trading profit. That does not mean none of your losses are used. This period's trading loss can be set against other profits, such as interest, in box 275. Your tax computation shows the unused balance, which carries forward while the trade continues. To carry an unused new trading loss back, enter Trading loss carried back in the loss-period return. We file the claim statement and tick box 45. A company with no trade cannot use a trading loss and does not see this box. Check your last tax computation for what an earlier unused loss is: an unused UK property business loss goes in Property losses brought forward, where it reduces total profits, and an unused non-trading loan relationship deficit goes in its own brought-forward field. A loss from a trade the company has stopped stays a trading loss and cannot be set against rent. The computation PDF shows the unused balance entering each return on its Trading losses brought forward row. If you expected an earlier loss balance on a single return or the first return of a long period and see £0, check the Trading losses brought forward field. For the second return, the row shows the first return's closing balance after relief.
What happens to a loss my company makes this year?
#Simple CompanyTax reports a trading loss arising this year on the CT600. After current-period relief and any entered carry-back claim, the unused balance normally carries forward while the trade continues. If the trade permanently stopped by the end of the return, tick “The company permanently stopped trading on or before [the displayed date]” at the bottom of Financial data. The computation then shows the unused amount as not carried forward. Separate terminal loss relief claims may be available but are not made by this service.
What happens to trading losses when my company stops trading?
Unused trading losses cannot carry into another period after the trade permanently stops. Tick “The company permanently stopped trading on or before [the displayed date]” for the last CT600 period so the computation shows the unused balance as not carried forward. This does not change the final period’s tax or mean there is no other relief. A final 12-month loss may qualify for terminal loss relief under section 39, while losses brought forward into the final period may qualify under section 45F. Those are separate claims that this service does not make.
Where do I find my losses carried forward for next year’s return?
Open the tax computation PDF and use the section called "Losses carried forward to the next period". It lists the remaining trading, UK property business and capital losses. Do not use CT600 boxes 780, 805 or 825 because those report amounts arising in the current period, not the running balance available next year. If your period has two returns, use the final return's closing figures. Do not add the two closing balances.
Some of my property losses are from before April 2020. Does that matter?
Not for a UK-resident company filing with us. Enter the full unused UK property loss in Property losses brought forward. The April 2020 restriction applies to certain non-UK-resident company landlords that moved from Income Tax to Corporation Tax, and those companies are outside our current scope.
My company made a loss but paid tax last year. Can I claim a refund by carrying the loss back?
Possibly, if an eligible current trading loss can be set against profit on which the company paid Corporation Tax in an earlier period. #Simple CompanyTax files your calculated preceding-12-month carry-back amount in the loss-period return or an amendment to it, adds the claim statement and ticks box 45. HMRC adjusts the earlier tax. An expected repayment in your accounts is a separate entry and does not make the claim.
My company trades and also lets property. Why is my capital allowances claim blocked?
We currently file every allowance and balancing charge entered by a mixed company against its trade. We therefore ask you to confirm the whole claim belongs to the trade. If any part belongs to the property business, we cannot safely split it from one total, so an accountant should file that return.
My AIA claim is over the limit. Why do you refuse it rather than cap it?
The excess is not AIA. It normally enters a pool for a writing down allowance, which needs figures we do not hold. Automatically capping the entry could lose the remainder or file a claim you did not make. Correct a typo, or use an accountant if the genuine claim exceeds the date-adjusted AIA limit.
Can my buy-to-let company claim capital allowances on a new boiler or appliances?
Usually not for equipment used inside a home the company lets, including a boiler or appliance in a flat and shared HMO areas. Equipment serving only the common parts of a block, or used in commercial property, may qualify. A system serving both common parts and individual homes needs the cost split, so work out the qualifying part or ask an accountant, then enter that figure. We file the figures you supply and do not confirm eligibility.
Failed property purchases and pre-letting costs
Are failed property purchase costs tax deductible for a limited company?
Costs that would have been capital on a successful investment-property purchase generally remain capital when it fails. Qualifying borrowing fees can have separate treatment. Identify what each cost was for rather than treating the whole amount as rental running expenses.
Can a company claim mortgage arrangement fees if the loan never completes?
Qualifying costs incurred directly in arranging the company’s borrowing can fall under the loan-relationship rules even if the company never enters into the loan. General investment advice or a survey for the purchase itself does not qualify merely because a mortgage was planned.
Can a property company make a UK property business loss before its first letting?
Preparatory costs do not automatically create a property business loss before the business starts. Qualifying pre-commencement revenue expenses may be relieved when letting begins. Separate borrowing costs can follow different rules. No rent in an established business is a different situation from never commencing.
Is Property disallowable expenses only for entertaining and fines?
No. With the separate rent and expense rows in SimpleCompanyTax, Property disallowable expenses is an add-back for costs already in the property expense rows that you have classified as non-deductible. Keep the expense in the accounts and enter the tax adjustment separately. Do not duplicate it in the trading Disallowable expenses field.
Where do abortive mortgage fees go in the filing wizard?
In SimpleCompanyTax, fees you classify as qualifying borrowing costs go in Interest payable and similar charges. Remove them from any other expense total to avoid duplication. For a company with no trade, the financing calculation is non-trading and separate from the property result. We explain the fields without deciding your accounting or tax treatment.
Why can my accounts show a loss when my property tax loss is zero?
The accounts include expenses that may not qualify for a tax deduction. Adding those costs back can eliminate a property tax loss while preserving the accounting expense. Moving qualifying borrowing costs into the finance heading can instead produce a separate non-trading deficit.
Why are the trading Disallowable expenses and Qualifying pre-trading expenditure fields hidden for a property-only company?
Those two fields adjust trading profit in SimpleCompanyTax. A company with no trade uses the relevant property and finance fields instead. This is a software distinction, not a statement that HMRC’s pre-commencement rules cannot apply to property businesses.
The filing process
Why does Trading status start on Dormant in the filing wizard?
A new filing starts with Trading status set to Dormant, so change it if that is not right for the period. Dormant hides the profit and loss sections and files the accounts and any CT600 as dormant, with no tax computation. Active is for a period in which the company had income, including bank interest, or business activity. HMRC and Companies House use different dormancy tests, so check both before you choose.
Which Filing purpose should I choose in the filing wizard?
Choose by what HMRC already has for this accounts period. If HMRC has nothing yet, choose Standard return, which files every CT600 the period needs. If HMRC already has your first CT600 with the full accounts and it is correct, choose File only the remaining CT600. To correct a return filed elsewhere, start from Amend filing made elsewhere.
Where can I find a guide for each choice in the filing wizard?
The filing wizard guides page lists a guide for each wizard choice and for common situations. Each guide says who the choice is for, when not to use it and the exact fields to fill in, with a fictional example and its tax result. The help icon beside each choice also links to its guide.
Why does the wizard say my accounting period cannot be in the future?
The accounting period end date cannot be in the future. Check the date and try again. Unfinished periods in the Accounting period list are greyed out. Choose the actual period you are filing that has ended, or use Custom dates to enter your correct dates. A resumed draft keeps its saved dates, so check those too. Do not shorten or fabricate dates to bypass the message.
What happens if my company's charitable donations are more than its profits?
Donation relief stops at nil taxable profits. Unused donation relief is usually lost, but if the company has an investment business and made the donations for its purposes, eligible unused relief joins its management expense pool automatically. Later use needs the investment business to continue. On Financial data, enter a current Charitable donations amount above £0, then use Unused donation relief below it, after the split panel for a long period. Choose Carried forward to reduce future profits (investment business only) when the conditions are met. With no non-zero management figures, blank means Not carried forward. Management figures infer carry-forward. Eligible return 1 relief can reduce return 2 profits. The linked article explains claims, historical periods and full HMRC conditions.
Charitable donations more than profits: can a company carry the relief forward? →
Do I have to tick box 75 on my CT600?
HMRC asks eligible businesses to enter an X in box 75. The SME exemption applies by law when its conditions are met. A blank box does not itself remove it or change a tax figure. The filing wizard records an optional answer for each return.
Can I tick box 70 and box 75 together?
No. HMRC does not allow boxes 70 and 75 to both be yes. Box 70 is a compensating adjustment claim and box 75 confirms SME transfer pricing exemption eligibility. This service supports box 75 and does not complete box 70.
How do I tick CT600 box 75?
In Financial data, find the checkboxes after Employees and tick Company qualifies for SME exemption from transfer pricing. In separate-figures mode, open Shared details. A single CT600 has one checkbox. Long Corporation Tax coverage has two dated checkboxes with independent answers. Check box 75 in each CT600 form PDF before filing.
How to tick CT600 box 75, the SME transfer pricing exemption →
Do transfer pricing rules apply to small companies?
Small and medium-sized enterprises normally have an automatic exemption from UK transfer pricing rules. Exceptions include non-qualifying territories, an election out of the exemption and certain HMRC notices. Include linked and partner enterprises when checking the size limits.
Do transfer pricing rules apply to small companies in the UK? →
What is CT600 box 75?
CT600 box 75 confirms eligibility for the small and medium-sized enterprise exemption from transfer pricing. Tick it if the company qualifies for that return. The optional declaration does not change the tax calculation.
How long does the filing process take?
Most micro-entity directors complete everything in 15–30 minutes. Dormant companies are faster, often under 10 minutes.
Can I start another filing while an earlier submission is awaiting a response?
Yes. Select New filing on the company card or Start new filing on the company page. If the card shows Resume filing, open its arrow and select Start new filing. This leaves a saved amendment available to resume later. You can start another period while HMRC or Companies House is still responding or only one has accepted. This opens a fresh form with Choose a period and blank dates. Resume saved filing reopens unfinished saved progress instead. Opening the new form leaves the saved copy unchanged. Saving it replaces unfinished new-filing progress for that company. Resume filing reopens the selected saved filing or amendment. To continue work on a rejected submission, use Re-file CT600 or Re-file Accounts on the company page. Previous filings and re-file work remain available there.
Can I save my progress?
Yes. Once the company has been added, select Save Progress at the top or bottom of the wizard, or select Next or Back to save your figures to your account. Check for Saved to your account before closing the page. Save times show BST in summer or GMT in winter, even when you are abroad. There is no automatic account saving. Changes since your last save stay only in the browser tab. A fresh form starts with Choose a period under Accounting period. Resume filing keeps your saved dates and reopens the latest account copy on another device. On the card, hover over Resume filing to check the saved period, date and UK time. Select its arrow to open Filing options on any device. The dropdown contains only Start new filing. This lets you start another filing while keeping a saved amendment available to resume. The company record shows these details beside its Resume button. Start new filing remains the purple action in the company-page header. New filing starts with blank dates and figures, even when the company has saved progress. Resume saved filing reopens that saved copy instead. Opening the new form leaves it unchanged. Saving the new form replaces unfinished new-filing progress for that company. If a company appears in both Personal and Practice, open its card in the workspace you want to use. Saved work belongs to that selected record. An older link that asks you to choose a workspace can be reopened from the dashboard. Before adding a company, progress stays in that browser tab only.
Can I submit a Company Tax Return using estimated figures, and when should I tick CT600 box 55?
HMRC allows estimated figures in some circumstances when final figures are not available despite the company’s best efforts. Use a reasonable best-estimate number, never placeholder wording instead of a figure. Select "This Corporation Tax return contains estimated figures" at the bottom of Financial data. #Simple CompanyTax marks box 55 on the CT600 and includes your optional explanation in the downloadable tax computation PDF. When an iXBRL computation is generated, the explanation appears there too. The selection does not change the figures or tax calculation.
How do I explain estimated figures on my CT600 (box 55)?
Tick "This Corporation Tax return contains estimated figures" at the bottom of Financial data, then use "Explanation of estimated figures" to say which numbers are estimated, why and when you expect final figures. HMRC expects an explanation. The field is optional in this wizard. Your words appear in the downloadable tax computation PDF and, when an iXBRL computation is generated, in the computation sent with the CT600. On a long period, one tick and explanation apply to both returns, so name the return if needed.
Can I leave a figure blank and tick box 55 until the final figure arrives?
No. Box 55 only tells HMRC that the return contains an estimate. It does not add anything to a figure or change the tax. A blank field is filed as nothing, so enter the company’s reasonable best estimate in the normal field, then tick This Corporation Tax return contains estimated figures and explain the estimate. HMRC’s manual says words such as information to follow instead of a figure do not meet the filing obligation. When the final figure is known, decide whether the return needs amending.
My company is several years behind with its Company Tax Returns. How do I catch up?
Each overdue accounts period is its own filing. File them one at a time, oldest first, with that period’s own dates and figures. Under Accounting period, a period marked (accounts filed) already has accounts at Companies House, so HMRC CT600 files only its CT600. A period marked (overdue) has late accounts at Companies House, and Companies House & HMRC CT600 sends both. Periods not in the list can be entered with Custom dates. This service files periods starting on or after 1 April 2015.
How do I correct a draft, rejected filing or accepted filing?
If it is still a draft, reopen it, edit the figures and generate a fresh preview. If a filing was rejected, correct the reason shown and submit it again because the authority did not accept it. If it was accepted, open the accepted filing and choose Amend this filing. An accepted Corporation Tax return needs an amendment, and a change to accepted annual accounts may need revised accounts.
What should I do if Review filing says my saved figures changed?
Keep a note of your latest edits and use one browser tab for that draft. Reopen it from your company page and check the dates and figures before continuing. If the message keeps returning, contact support with your company number and the message shown. Do not change correct figures or dates just to get past the message. Clicking Review filing does not submit a return.
Why am I being asked to review my filing again?
A preview is a snapshot of the figures you reviewed when it was generated. Before anything is sent, we check that your saved figures still match that snapshot. If they do not, the filing dialog offers Reload saved figures. It opens the same filing on the Review page with the figures as they are saved now, so you can check them, generate a fresh preview if you want new documents, and continue. Viewing or downloading a PDF does not create a new preview. Nothing is filed until you authorise it.
My filing was stopped before it was sent. What does that mean?
We found a problem that would have caused HMRC to reject the return, so nothing was sent. Correct the named figure in the wizard and file again. There is nothing to withdraw and no extra charge to resubmit. If you believe the figure is right, contact support with the filing reference.
Why is my CT600 or Companies House filing pending?
Pending means we have not yet confirmed a final acceptance or rejection. HMRC and Companies House decide separately, so one side can be accepted while the other remains pending. Customer outcome emails are reserved for an HMRC acceptance or rejection, not internal status-checking limits. Keep the filing reference and check the filing page rather than submitting the same documents again.
Does a completed job mean HMRC and Companies House accepted my filing?
No. Check the acceptance response for each authority you chose. A generated preview has not been filed, and an acknowledgement is not final acceptance. If you filed two CT600 returns, check both responses. The Documents page shows Filing accepted only when every authority and every return in that submission has been accepted. Earlier attempt not accepted means a later accepted submission completed the outstanding filing. Any authority that already accepted its part stays accepted, so no action is needed for the earlier attempt. Acceptance not confirmed can also mean an older receipt cannot be matched to this submission, not that the filing was rejected or its acceptance changed. Check your receipts or contact support before submitting again.
What does Rejected mean, and where can I see the reason?
Rejected means the named authority did not accept that part of the filing. Open the filing record to see whether HMRC, Companies House or both rejected it, together with the exact rejection details and filing reference. Correct the stated problem and submit again. If one authority accepted its documents, do not send that accepted part again unless it also needs correcting.
Are my accounts filed if my dashboard shows a future deadline?
A future deadline does not prove a previous filing was accepted. Check the relevant receipt and Companies House filing history. An overdue deadline is not cleared by starting a draft or buying a subscription.
Which payment deadline applies if my company pays Corporation Tax by instalments?
Can I correct the dates of my prior-year comparative figures?
Yes. Previous-period dates are prefilled from the Companies House record where possible, or suggested using the preceding twelve months. You can continue with those dates or edit them to match the figures. The previous period must end before the current period starts. Your entered figures are preserved, and the existing review shows the dates before you approve the filing.
Why is my taxable profit different from the profit in my accounts?
Accounting profit follows the accounts rules. Taxable profit starts from that result and applies Corporation Tax adjustments, such as adding back disallowable expenses and depreciation, then deducting qualifying capital allowances or reliefs. A difference is normal when the adjustments are correct.
Where do I enter other Corporation Tax adjustments?
On Financial data, open Tax adjustments and select Show all adjustment options above or below the table. The most commonly used options appear first. Related controls appear automatically when needed. Options with figures or an error stay visible when you show fewer options. Leave optional fields blank when they do not apply. For a long accounting period, use the allocation controls shown for both returns.
Other software asked me to itemise salaries, audit fees and office costs. Why does this not?
Because we prepare the shorter FRS 105 micro-entity format, which reports expenses under a small set of statutory headings rather than a long itemised list. Salaries and other payroll costs are the exception: company law shows them as their own Staff costs line, which is why we ask for them separately. Professional fees, rent, insurance and office costs need no lines of their own and go in Other charges. The CT600 also reports turnover and trading profit rather than separate office, salary or accountancy-fee boxes. Enter depreciation in its own field so we add it back for tax, and keep the underlying records in case HMRC asks for them.
Where do I enter a bad debt or an unpaid invoice I have written off?
If your completed accounts include a bad-debt or trade-debtor impairment expense, enter that expense in Other charges. Our form uses the statutory micro-entity headings, so there is no separate Bad debts line. Include your current and previous period Debtors balances in the Current Assets totals exactly as shown in those accounts. Do not use the Depreciation and amounts written off assets field, which covers fixed assets and is added back for tax. If you have not yet worked out the accounting or tax treatment of the debt, an accountant can confirm it.
Where do I enter income that has no obvious box, like a one-off fee?
Use the Income not falling under any other heading row in the profit and loss step. It is for taxable receipts that fit no other row, such as a one-off referral or introduction fee earned outside your normal business, another casual one-off receipt, or a fixed cash bonus from your business bank. Enter the amount and we file it in CT600 box 205, within Other income in your accounts. We trust your classification, so use another category when one fits. Income your company earns as part of its normal business is turnover, not other income.
Why did my brought-forward trading losses not reduce the tax on my other income?
Same-trade-only losses use CT600 box 160 and cannot reduce other income. Eligible post-2017 trading losses can be claimed against total profits, including box 205 income, using box 285. Enter the full opening pool under Trading losses brought forward, identify the restricted part and check the maximum claim shown. Blank claims the maximum, while 0 claims nothing. The trade-continuation and other statutory conditions still apply. Reopen and save older drafts to use these controls.
Why does my P&L show 19% when Corporation Tax due is £0?
The percentage is the calculation’s rate-band label, not an extra charge. Read the pound amount on the Corporation tax row and on Review & file. If both show £0, the figures agree. A £400 loss before tax stays a £400 loss after a £0 tax charge.
What is the difference between leaving the box 285 loss claim blank and entering 0?
Blank claims the maximum shown, so eligible brought-forward trading losses reduce this return’s total profits as far as they can. Entering 0 makes no box 285 claim, so those losses all carry forward and the profits stay taxable. With £30,000 of eligible losses against £22,000 of profits, a blank claim gives £0 of tax and 0 gives £4,180. How much to claim is your decision.
Is cashback or a bank switching bonus taxable for a limited company?
Yes. Cashback and rewards a company receives on its business banking are taxable, even though similar rewards on a personal account usually are not, because companies are taxed on their profits under different rules. How you record it depends on what it was: cashback earned on business spending is a rebate, so reduce the expense it relates to, while a standalone reward such as a switching or joining bonus is income and goes in box 205. Anything worked out from your balance or an interest rate is interest and belongs in Interest receivable. Cashback earned on a director personal card belongs to the director and is not company income at all.
Where do I enter cashback or a bank reward? I cannot see an other income box.
Cashback earned on business spending is normally deducted from the expense it relates to, so reduce Other charges or Cost of raw materials by the amount, and there is nothing else to enter. A fixed promotional cash reward paid separately by your business bank, and not calculated as interest, is taxable and goes in the Income not falling under any other heading row, which files in CT600 box 205 and appears within Other income in your accounts. Anything worked out from a balance or interest rate is interest and belongs in Interest receivable instead.
Where do I enter charitable donations?
Enter the payment once in Charitable donations in step 2, Profit and loss. Exclude it from trading and property Other charges and any net property income figure. We include it in the accounts automatically, add it back for tax and claim the available relief in CT600 box 305. Leave blank if none. Prior-year donations go in the prior-year cell and do not affect current-year tax. The field supports cash gifts to a UK registered charity or registered CASC where the company and connected people received nothing in return. For two Corporation Tax returns, assign the donation using the payment dates in the panel below the field.
Charitable donations and Corporation Tax relief, explained →
Where do I enter entertaining, fines and other disallowable expenses?
Enter the cost in both places. Leave it in the relevant expense total so the accounts show the real cost, then enter the same amount in Disallowable expenses under Tax adjustments. We add it back when calculating taxable profit. A £1,000 fine normally appears in Other charges and as £1,000 of disallowable expenses.
My accounting period is longer than 12 months. Which Corporation Tax return do I claim pre-trading expenses in?
Qualifying pre-trading expenditure is deducted in the return covering the day trading began, not divided by days. Enter the qualifying total once, then enter the allocation in the split panel immediately below Qualifying pre-trading expenditure and select Confirm this split. Check the dates and amounts for both returns before submitting. Do not enter costs already deducted through your expense figures again. If your accounts period is long but your Corporation Tax coverage needs only one return, no split is needed.
Can I claim costs from before my company started trading?
Yes, if the company incurred them and they qualify. Revenue costs from the seven years before trading began, incurred wholly for the trade, are treated as spent on the first day of trading and reduce the taxable profit or increase the trading loss of the period trading started. If the costs were expensed in an earlier year's accounts, before the trade existed, enter the qualifying total in the Qualifying pre-trading expenditure field under Tax adjustments and we deduct it in the tax computation without changing your accounts. Costs already inside this year's expense figures are being deducted through those figures, so do not enter them again. Costs from before the company was incorporated are not automatically company expenditure, and company formation fees are capital.
How do I record or release a provision for liabilities?
Provisions are entered as closing balances, not journals. On the balance sheet step, use the link that adds the optional lines to reveal Provisions for liabilities, then enter this year’s closing provision and last year’s in the prior-year column. To release a brought-forward provision, enter last year’s figure and the reduced balance, or zero, for this year, and include the effect of the release in your expense figures. If the provision was previously disallowed for tax, contact us with the details before filing and we will confirm whether it fits the supported route while we review support for that case.
What do I enter for capital allowances?
Enter each claim separately under Tax adjustments. Use AIA for qualifying equipment bought in the period, then record any special rate part in the field beneath it. Fixtures like wiring, heating and air conditioning DO qualify for AIA when bought this period, so they go in the AIA figure and that field only records how much of it they are. Use the separate fields for writing down allowances, a qualifying new electric car, structures and buildings allowance or balancing charges. Cars never qualify for AIA, and full expensing or other unsupported first year allowances need an accountant.
How do capital allowances work when my first accounting period is longer than 12 months?
We show both Corporation Tax return date ranges and ask you to assign each capital allowance, pool addition and balancing charge between them. The suggested day-count split is only a starting point. Change it to match the actual purchase or sale dates, then confirm that both amounts add back to the total.
Where do I enter a balancing charge for an asset I sold?
Enter any accounting profit on the sale in Profit on disposal of fixed assets, then enter the computed balancing charge in the main or special rate pool field under Tax adjustments. Work the charge from the disposal value and pool balance, not directly from the sale price. Any taxable amount above original cost is a chargeable gain rather than a balancing charge.
My company gets rental income from property. How do I enter it?
Enter rent for the accounting period before expenses in Property rental income. Enter rental costs in Property income and expenses and mortgage interest separately in Interest payable. If the company also trades, enter trading costs in the separate trading section. Older net-only drafts keep their existing meaning unless you choose to enter gross rent and separate expenses.
How do I split expenses when my company trades and rents out property?
Enter trading costs in Trading income and expenses and letting costs in Property income and expenses. For shared costs, enter your allocated amount in each section without duplication. Enter property tax adjustments under Property tax treatment. We combine the business figures for annual accounts and use your classification without asking for evidence.
How is my company's property tax base calculated?
We calculate it from your rent and property costs, with the property tax adjustments you enter. Interest, capital allowances and brought-forward losses have their own fields. There is no property tax base override. If you need an adjustment we do not offer, contact us before filing. An amendment of an older return with an entered base uses the calculated base and shows the original figure as no longer used.
My company sold a property or investment at a profit. Can I file the gain?
Yes, for a straightforward chargeable gain that you have calculated. Enter the gross gain and current or brought-forward capital losses under Tax adjustments, and enter the accounting profit on disposal separately for the accounts. Connected-party sales, potentially exempt share disposals, ATED-related gains and non-resident cases need an accountant.
Our company owns property and UK listed shares. Can you file our return?
Usually, if the company qualifies as a micro-entity. Associated companies are fine: you enter how many. Enter rent, dividends, investments and any chargeable gain in their separate fields. FRS 105 records property and shares at cost rather than market value, and you must calculate any share disposal gain using the applicable pooling rules.
Can we show our investment property or shares at market value?
No. Our FRS 105 accounts carry investment property at cost less depreciation and impairment, and investments at cost less impairment. Enter what the company paid, not today's market value. If you need fair-value or revalued accounts, you need FRS 102 Section 1A accounts and an accountant.
Where do I enter share premium? The help text says not to add it to share capital.
Enter share premium and other non-share-capital reserves in Retained earnings. Keep Share capital to the nominal value of issued shares so it matches the Companies House register. FRS 105 filed accounts show one combined Capital and reserves total, but share premium is still not a distributable profit.
My shares were issued but never paid for. What do I put for share capital?
Enter the nominal value in Share capital and the unpaid amount in Called up share capital not paid. For one unpaid £1 subscriber share, enter £1 in each field. Do not reduce Share capital to zero or put the unpaid amount in Debtors because an issued share remains on the register and the unpaid amount has its own statutory balance-sheet line.
Where do company running costs go if the company has no trade?
For property activity, enter gross Property rental income and prepared costs in the separate property expense rows. Older drafts labelled Income from property (net) retain net entry or offer Enter gross rent and separate expenses. Investment-management expenses have a different treatment. Do not also claim costs already included elsewhere. You determine the treatment before entering the figures.
The company received dividends from another company. Are they taxed?
You determine which dividends are taxable or exempt. Enter the full amount in Dividends received, then complete Of which taxable dividends and its non-UK subset. Enter qualifying exempt group dividends in their own subset field. These are parts of the total, not extra income. For two returns, confirm the allocation below the dividend rows and check both computations.
What formats do you deliver?
Your filing record contains the submitted CT600 XML, the full iXBRL accounts for HMRC, the iXBRL accounts filed to Companies House, the iXBRL tax computation and regulator receipts. By default the Companies House copy is filleted, meaning the balance sheet, statements and notes with the profit and loss account withheld. If you chose to publish the profit and loss account, the Companies House copy is the full accounts, identical to the HMRC copy. You also get readable PDFs of the official CT600 form, both accounts versions and the tax computations, with page numbers. The exact set depends on whether you filed to HMRC, Companies House or both.
Where can I download a draft, accepted filing documents or filing receipt?
Open the company and expand its Filing Timeline. Draft previews appear under Drafts and accepted filings appear under Filed records. Choose Documents or View filing record to view and download the available PDFs, submitted files and regulator receipts. If the filing has two Corporation Tax returns, check that both HMRC responses are present.
What date should I enter as the accounts approval date?
Enter the date the directors approved the finished annual accounts. We default it to today, but you can change it. It cannot be before the accounting period ended or in the future. The date appears on draft and final accounts. It can differ from CT600 box 980 because that box records the return declaration date, which is the preview date on a draft and the HMRC filing date on the final CT600 PDF.
Which approval dates do I enter for revised accounts?
On the review page, enter the date the directors approved the revised accounts in Date directors re-approved the revised accounts. Enter the date printed on the original accounts in Original accounts approval date when you preview or submit, not the date they were filed. If you change a date after downloading a draft, generate a fresh preview and check both dates before filing.
How do I choose where to send a CT600 amendment?
For a return filed elsewhere, File this amendment to starts with your answer to What are you filing? in Company & period. You can change it before filing. On Review & file, select HMRC, Companies House or both under File this amendment to before choosing Continue to submission. If neither is selected, the amendment stays saved as a draft. Enter Reason for amendment using 16 to 500 characters. If Companies House is selected, choose the filing kind. For Revised accounts or Replace filleted accounts with full accounts, enter Date directors re-approved the revised accounts before Continue to submission or Preview your documents (free). Filing credentials shows the review destinations read-only. Close it and use File this amendment to to change them. The authorised amendment details are saved before sending. If it cannot be saved, nothing is sent and you can try again. These destination choices also apply to a long accounting period with two CT600 returns.
Why can I not continue my CT600 amendment?
Enter Reason for amendment using 16 to 500 characters to describe what is being corrected and why. If Companies House is selected, choose the filing kind. For Revised accounts or Replace filleted accounts with full accounts, enter Date directors re-approved the revised accounts using a real date on or after the period end and no later than today. Complete these before Continue to submission or Preview your documents (free). Continue to submission also needs HMRC, Companies House or both selected under File this amendment to. A free preview can have no destination. These requirements apply to the whole amendment, including a long period with two CT600 returns.
Why do my revised accounts include a statement and my reason for the revision?
The Companies (Revision of Defective Accounts and Reports) Regulations 2008 require revised accounts to state, in a prominent position, that they replace the original accounts, that they are now the statutory accounts, that they were prepared as at the date of the original accounts, the respects in which the original accounts did not comply and the amendments made, and the date the directors approved the revision. We print these on a separate final page headed Revised accounts statement, in the same plain style as the rest of the accounts, with the cover marked Revised. Nothing requires a box or a warning. Your reason is printed once, so keep it to a short factual description of what was corrected.
How do I correct a CT600 I filed with #Simple CompanyTax after it was accepted?
Open the accepted filing and click Amend this filing, or click Amend filing on that period on the company page, then Proceed to amendment. We copy your filed figures into a new draft. Change what was wrong, enter a Reason for amendment of 16 to 500 characters and tick HMRC, Companies House or both under File this amendment to. Ticking HMRC sends each CT600 from the original filing as an amended return. For an accounts period longer than 12 months, both CT600s are sent again as amended returns. The accounts period and Corporation Tax dates cannot change in an amendment.
How do I file revised accounts at Companies House?
If Companies House accepted accounts you filed with us, start an amendment from that filing. On the review page, tick Companies House under File this amendment to, choose Revised accounts and enter Date directors re-approved the revised accounts. When you preview or submit, also enter the Original accounts approval date. We add the revised accounts statement the 2008 Regulations require, and your original accounts stay on the public register. With only Companies House ticked, no CT600 is sent to HMRC. Revised accounts are for the same accounts period as the original, including a period longer than 12 months.
Why did HMRC reject my amendment with error 1611?
Error 1611, No original Return yet recorded, means HMRC could not find the original CT600 to amend. If you amended soon after filing, HMRC may not have recorded the original yet. Wait for HMRC's own confirmation email, usually from the sender Gateway Confirmation, then submit the amendment again from its filing page. For a return filed elsewhere, check that the UTR and the exact period dates match HMRC's record. If no original was ever filed, start a new filing instead.
My first accounting period is longer than 12 months. What do I do?
Enter the full accounts period. You can choose separate figures for each return. With Enter my figures once, if the company was within the charge to Corporation Tax for the whole of it, we create the two Corporation Tax returns HMRC requires and one set of Companies House accounts for the full period. The standard CT600 dates are calculated for you. If the first end differs from HMRC, open Change CT600 split date and edit First CT600 ends. The second starts the next day. Income and running costs are shared by day count using those dates. If you have capital allowances or a balancing charge, confirm which return contains the purchase or sale instead of relying on the suggested split. If the company was dormant at first and started trading later, check your CT603 notice: HMRC expects one return from the trading start only where their records show that later date.
My company was dormant and started trading later. Which periods do I enter?
Enter your full annual accounts period, from incorporation in a first year or from your year start in a later year, up to the Companies House year end. If your HMRC business tax account and CT603 notice show one Corporation Tax return from the date trading started to that same year end, select the separate HMRC period option and enter the later start date. We attach the full accounts and select CT600 box 85. A later year keeps its comparative figures as normal. If HMRC also asks for a dormant-period return, this one-return route does not apply.
Why is my Corporation Tax higher after I entered a later Corporation Tax start for a dormant company?
Because the return is shorter. The full accounts figures are taxed in the Corporation Tax period HMRC shows, and HMRC reduces the £50,000 and £250,000 profit limits for a period shorter than 12 months. A profit that would be taxed at 19% over a full year can fall between the reduced limits, so the review card shows the 25% main rate with marginal relief. The figures are not reduced by days. The dates you enter should be the dates HMRC expects.
I changed my company year end. What do I do about the CT600?
Change the accounting reference date with Companies House first, then check the Corporation Tax period dates HMRC has set. If the full accounts period is over 12 months and up to 18 months, enter it once. SimpleCompanyTax prepares one set of annual accounts and the two CT600 returns HMRC requires. Use confirmed dates, not guessed dates.
Why is an expense split between my two Corporation Tax returns?
With Enter my figures once, ordinary whole-period income and running costs are divided by days between two CT600s. Claims and events with allocation panels, such as capital allowances, donations, dividends received and gains, follow the amounts you confirm instead. Alternatively choose separate figures and enter prepared period figures directly in each CT600 tab. Review both computations. The guide distinguishes the day-split expenses from the entries requiring a dated allocation.
HMRC says my first CT600 ends earlier than the dates the wizard shows. What do I change?
Change only First CT600 ends. On Company Profile & Period, click Change CT600 split date beside the two CT600 dates and enter the last day of HMRC's first period. The second CT600 starts the next day. Keep your full accounts dates as they are. Both CT600s are still sent, and neither may cover more than 12 months.
What does Enter my figures once do?
It uses one set of figures for your accounts and your CT600s. When there are two CT600s, recurring income and costs are shared between them by the number of days in each. Each amount on an allocation panel, such as a dividend, gain or capital allowance, follows the split you confirm. Enter the totals for the whole accounts period, not just the first 12 months.
What does Enter figures separately do?
It keeps your statutory accounts figures for the accounts and uses your own prepared figures for each CT600. Nothing is shared between the returns by days, and the allocation panels are not shown. Enter each CT600's figures for its own dates only. Typing the whole period's figures into both CT600 steps taxes the same profit twice.
My company's first accounts cover more than 12 months. Which options do I choose in the wizard?
Choose the full first accounts period, Standard return under Filing purpose, Active under Trading status and Enter my figures once, then enter the figures for the whole period. The wizard prepares two CT600s, normally the first 12 months and the remaining days, and one set of accounts. Leave the HMRC Corporation Tax period checkbox unticked unless HMRC's period starts later than your accounts, for example after a dormant start.
Do you file to both HMRC and Companies House?
Yes, for supported company filings. You review the documents, enter your own filing credentials and select Submit. The platform sends the filing to the destinations you selected. Support staff do not send it manually. Check each authority’s response separately. CIC accounts use a separate package that you upload to Companies House yourself.
Can I submit my CT600 and accounts with my own credentials, without support staff filing for me?
Yes. You choose the filing destinations, review the documents and enter the credentials in the final filing window. When you confirm the declaration and select Submit, the platform sends the filing automatically. Support staff do not manually submit it. Enter the Government Gateway details for the company’s Corporation Tax account for HMRC and the company authentication code for Companies House. Never email your password or authentication code to support.
I’ve already filed my accounts to Companies House. Can I file just the CT600 to HMRC?
Yes. Under Accounting period, choose the period your CT600 covers, normally the one marked (accounts filed), or use Custom dates. The help icon beside Accounting period explains these choices. For accounts longer than 12 months, choose the full accounts period. The label describes Companies House records, not HMRC filing history. Then under What are you filing?, choose HMRC CT600. After you approve the filing and select Submit, the platform sends only the Corporation Tax return. The final step asks only for HMRC credentials. This works whether the accounts were filed through this service or elsewhere. If you change the destination after generating a preview, generate a new preview before submitting.
Does editing the office address on my return change my registered office at Companies House?
No. Edit Office Address in Company & period only updates the address on the submitted return. To change your registered office, file form AD01 with Companies House. The help icon beside Edit Office Address links to the official AD01 page.
Can I file only my accounts to Companies House (not the CT600)?
Yes. In step 1, choose Companies House under What are you filing? Review the accounts, then enter the company authentication code in the final filing dialog. Check the Companies House outcome afterwards. Filing accounts alone does not fulfil a separate CT600 obligation.
What does each choice under What are you filing? send?
HMRC CT600 sends only the Corporation Tax return to HMRC, with the accounts and tax computation inside it, and nothing to Companies House. Companies House sends only the annual accounts to Companies House and no CT600. Companies House & HMRC CT600 sends both from one set of figures, and it is what the form starts on. If the period list shows (accounts filed), Companies House already has those accounts, so choose HMRC CT600 to avoid sending them again. File only the remaining CT600 needs HMRC CT600.
I don't have a Government Gateway account set up for Corporation Tax. How do I create one?
Sign in to HMRC online services, or create new Government Gateway sign-in details, then add Corporation Tax to your business tax account using the company registration number and 10-digit UTR. HMRC posts an activation code to the registered office within 10 days, so start well before the filing deadline. Use the account that has Corporation Tax for the company you are filing, not a personal tax account.
HMRC says my sign-in details are wrong but I am sure they are correct. What now?
HMRC uses the same Authentication Failure message for several problems. Sign in with the same Government Gateway ID and check that Corporation Tax is listed, the enrolment is active and the 10-digit UTR matches the company you are filing. Spaces copied into Gateway User ID are removed automatically. Letters, digits and punctuation are preserved, and your password is unchanged. Check each authority before retrying and re-file only the one that rejected the filing. For a long accounting period, Re-submit to HMRC sends both CT600s again.
My company's UTR does not appear in my HMRC online account. What do I do?
If Corporation Tax is missing, add the service and activate it with the code HMRC sends. If another company's UTR appears, use the Government Gateway account enrolled for the company you are filing. If HMRC holds the wrong link, contact the HMRC Online Services Helpdesk. The Corporation Tax UTR is a 10-digit company reference, not your personal UTR or company registration number.
Where can I find my company UTR for Corporation Tax?
Your company UTR is the 10-digit Corporation Tax reference on HMRC letters, previous Company Tax Returns and your Business Tax Account. It is not your personal UTR or Companies House company number. If you cannot find it, request a Corporation Tax UTR online and HMRC will send it to the business address registered at Companies House.
How do I change an incorrect UTR or Government Gateway ID before filing?
Enter the correct 10-digit Corporation Tax UTR and Government Gateway details in the final filing window. You can edit the prefilled UTR before submitting. For both companies and unincorporated clubs, the edited UTR is saved on the same filing and prefilled when you reopen it. It does not change the saved business record. If a submission was rejected for incorrect sign-in details, correct the details before trying again. Never send your Government Gateway password by email.
What is a Companies House authentication code? Is it the same as my personal code?
The company authentication code is a 6-character code that authorises online filings for one company. It is not the Companies House personal code used for identity verification. Request it through Companies House WebFiling if you do not have it. It is posted to the registered office, or to your home address if you cannot access the registered office.
Companies House says my authentication code is invalid. What should I do?
Your accounts were not filed with Companies House. Check that you entered the current six-character company authentication code, not your personal code or WebFiling password. On your filing page, choose Re-file accounts and enter the company code again under Authentication code. If you do not have it, request it from Companies House. It can take up to ten working days to arrive. Your accounts filing deadline still applies.
Do I enter my Government Gateway details twice when my accounts period needs two tax returns?
No. When your accounts period ends more than 12 months after it starts, you enter the Corporation Tax UTR, Gateway User ID and Gateway Password once in the Filing credentials dialog. We send both CT600s to HMRC with those same details, one after the other, and the filing page shows each return on its own row with its own status.
HMRC rejected both returns for my long accounting period. Do I resubmit each one separately?
No. Both returns were sent with the same Government Gateway details and UTR, so an Authentication Failure usually shows on both. Sign in to HMRC and fix the account or the details first, then choose Re-submit to HMRC on the filing page. That sends both CT600s for the period again with the details you enter, including any return HMRC has already accepted.
Why does the filing dialog say my UTR must be 10 digits?
A Corporation Tax UTR is always 10 digits, and the field accepts digits only. A shorter number, such as a company number or part of a UTR, keeps Submit grey and shows how many digits you entered. Find the 10-digit UTR on HMRC letters about Corporation Tax or on a previous Company Tax Return. A personal Self Assessment UTR is also 10 digits, but HMRC refuses it for a company CT600.
Why is there no authentication code box in my filing dialog?
The Authentication code field only appears when Companies House is ticked under Filing targets in the Filing credentials dialog. A CT600 sent to HMRC only does not need it. Clubs, charities and community interest companies cannot select Companies House in that dialog, and their Companies House card explains why.
What credentials do I need to submit, and where can I find them?
You will be asked for the relevant details at the final step, immediately before filing.
For Companies House (statutory accounts filing):
You will need your company's 6-character Companies House authentication code. This code is sent by post to your registered office address. If you do not have it, you can sign in to Companies House WebFiling and select “Request an authentication code”. It can take up to ten working days to arrive, so request it well before the filing deadline.
For HMRC (Corporation Tax return filing):
You will need:
- Your company's 10-digit Corporation Tax Unique Taxpayer Reference (UTR)
- The Government Gateway user ID and password for an account that is enrolled for Corporation Tax for the company
Your Corporation Tax UTR can be found on HMRC Corporation Tax correspondence or within your Business Tax Account. If you have forgotten your Government Gateway user ID, you can recover it through the HMRC online services portal.
For security, your credentials are used only for this submission and are never stored. Your Government Gateway details and your Companies House authentication code are both transmitted for the filing and then discarded. You re-enter them next time you file.
You also confirm the director approving the accounts and the accounts approval date. Those details appear in the accounts and are saved with the filing.
Will my turnover and profit be public when I file my accounts?
Companies House receives filleted accounts without the profit and loss account by default. Where that option is shown on the filing page, you can choose to publish full accounts including the profit and loss account. Those income and expense totals then become public. HMRC receives the full accounts and computation with a Corporation Tax return. The linked guide separates current choices from announced future changes.
Why can I not put my car in the Annual Investment Allowance field?
Cars are excluded from AIA. Use the main or special rate writing down allowance according to the car's CO2 emissions, or the separate 100% field for a qualifying new zero-emission car. Vans and other commercial vehicles are not cars for this rule and can qualify for AIA.
Do the "Added to the pool this period" fields change my tax?
No. They are cost disclosure only. HMRC asks the return to report what the company spent on assets that went into a pool this period, in boxes 770 and 775, alongside any allowance claimed. Your tax comes from the allowance fields, and you report an addition whether or not you claim a writing down allowance on it this year.
What does "Of which is special rate items" under the AIA field mean?
It is the part of the AIA total spent on special rate items, such as integral features, solar panels, thermal insulation and long-life assets. It is included in the AIA figure above, not added to it. Cars never belong here because they cannot use AIA. We ask only because HMRC reports each pool's share separately.
Why is my car's cost not in box 770?
Because HMRC excludes special rate cars from box 770 and has them reported in box 775 instead. Box 770 covers the rest of your special rate spending, such as integral features, solar panels and long-life assets. When you tell us the cars part of your special rate additions, we move that part to box 775 for you. It does not change your tax, only where the cost is disclosed.
Do I still work out the structures and buildings allowance myself?
No. Add one claim line for each amount on the allowance statement and enter its qualifying expenditure and dates. We calculate the ordinary 2% or 3% annual allowance, including a blended rate across April 2020 and separate calculations for two returns in a long first period. The tax computation shows the working.
Can SimpleCompanyTax file the enhanced 10% structures and buildings allowance?
No. Enhanced 10% SBA for qualifying freeport or investment-zone expenditure needs CT600M, which we do not produce. We support ordinary 2% or 3% SBA. If the allowance statement identifies a special tax site or enhanced claim, do not reclassify it as ordinary. Ask an accountant to file it.
Why do you ask for the building's cost every year when box 771 is only for a first claim?
The yearly allowance is calculated from the qualifying expenditure on the allowance statement, so we need that cost every year. We only put it in box 771 when you identify the return as the first claim. In a long first period it is reported once, on the first return in which that claim accrues.
Is the main pool writing down allowance still 18%?
It depends on your dates. The rate is 18% a year for accounting periods ending before 1 April 2026 and 14% a year for periods starting on or after that date. A period that straddles 1 April 2026 uses a hybrid rate between the two, and GOV.UK publishes a guide for working out the exact blended figure. The special rate pool is unchanged at 6% a year, and it was 8% a year before April 2019.
After you file & paying HMRC
I made a mistake on a return I already filed. Can I correct it?
Yes. Open the accepted filing and choose "Amend this filing". Change the pre-filled figures, explain the correction and select whether HMRC, Companies House or both need the revision. On the review page, choose Continue to submission. The final button names the destinations you selected. HMRC amendments normally close 24 months after the accounting period ended. A rejected filing has not been accepted, so correct it and submit again instead.
Why does Amend filing made elsewhere not ask for my company details?
The details come from your existing company and Companies House. In Company & period, check the company details and registered office, then choose the period you are amending from the list or use Custom dates. You are asked for Period start and Period end before the wizard only when Companies House has no accounting dates for the company. Enter those dates and select Continue.
Why is the registered office blank when I amend a return filed elsewhere?
When you select Amend filing made elsewhere on your company page, the wizard fills the registered office from Companies House. Check and edit it in Company & period. If Companies House has no address or the lookup failed and there is no stored address, enter it yourself in that step. The address you leave in the wizard is saved with your filing.
When will my Corporation Tax show in my HMRC account after I file?
Usually within a few working days after HMRC accepts the CT600, although HMRC does not guarantee a timescale. Your SimpleCompanyTax acceptance record already shows the tax figure, so you can pay with the correct accounting-period reference without waiting for the online balance to update.
Can I pay HMRC before the amount shows in my account?
Yes, and you often should. Corporation Tax is self-assessed, so you can pay as soon as you know the figure (your filing receipt shows it) without waiting for the portal to update. As long as you use the correct 17-character payment reference for the accounting period, HMRC matches your payment to the right period. This matters because the deadline to pay is earlier than the deadline to file.
Do I need to choose the accounting period when I pay?
Effectively yes, and you do it through the payment reference. There isn't a separate "which year?" step. The 17-character reference is how HMRC knows which accounting period your money belongs to. Use the reference for the period you're paying and the payment lands against that period. Paying the right amount with the wrong period's reference is the most common mistake.
Is my Corporation Tax payment reference the same every year?
No. HMRC gives each accounting period its own 17-character payment reference, and it changes with each period. Your 10-digit UTR stays the same, but the payment reference does not, so do not reuse last year's. If your bank saved HMRC as a payee, update the saved reference. Find the correct one on your notice to deliver your tax return, on an HMRC reminder, or in your HMRC online account under the Corporation Tax statement and accounting periods.
My accounts period is longer than 12 months. How many Corporation Tax payments do I make?
Usually two. A period over 12 months is filed as two CT600s, and each return is its own accounting period with its own payment deadline, 9 months and 1 day after that return ends, and its own 17-character payment reference. The Review & file page lists the deadlines as CT payment due (Return 1) and CT payment due (Return 2). Pay each return's amount under its own reference rather than one total under one reference.
How do most people pay their Corporation Tax, and by when?
Most companies file, then pay HMRC directly by bank transfer using that period's 17-character reference. Corporation Tax is usually due 9 months and 1 day after the accounting period ends, while the CT600 is due after 12 months. SimpleCompanyTax files the return but does not collect the tax.
How do I tell HMRC this is my final CT600 because the company has stopped trading?
There is no final-return box. Set the CT600 period to end when trading stopped and tick “The company permanently stopped trading on or before [the displayed date]” at the bottom of Financial data. If that date differs from the statutory accounts end, choose “HMRC CT600” under “What are you filing?”. This route does not file Companies House accounts. Tell HMRC separately if the company has become dormant. If you are closing the company, follow the strike-off process as well.
HMRC sent my company a tax determination. What should I do?
A determination is HMRC's estimated Corporation Tax bill because a required CT600 was not filed. It is not the company's final tax calculation. Identify the period, file the accurate return and pay the tax due promptly. You may be able to appeal a late-filing penalty, but HMRC says to file the return first.
Data & security
Where is my data stored?
On managed UK cloud infrastructure. Data is encrypted at rest (AES-256) and in transit (TLS 1.2+).
Can I delete my data?
You can request deletion of your account and personal data. We may still need to retain filing records for the period required by tax, accounting and legal obligations, which is generally at least 6 years. Our Privacy Policy explains the retention rules and your rights.
Do you sell my data?
No. Never. Our Privacy Policy sets out exactly how we process and share data.
Still have a question?
Support responds within one working day, sooner if your filing deadline is close.