Does it support your accounts format?
We generate FRS 105 micro-entity accounts. FRS 102, consolidated and audit-required accounts are outside this service.
CT600 software: choose the right filing service
The right choice for your small business depends on its accounts format, tax return and filing destinations. This checklist helps you compare those needs with what SimpleCompanyTax supports.
Written by the software supplier. Last checked: .
Check the software supplier and filing scope
SimpleCompanyTax is listed as “SimpleCompanyTax” on HMRC’s Corporation Tax commercial software supplier list for CT600 production/submission, iXBRL documents and self-filers. HMRC does not recommend or endorse one listed supplier over another. Check what each supplier supports for your particular return.
What to look for in CT600 software
Use these questions when choosing software for micro-entity accounts or a supported charity/club return. You prepare the figures and choose the tax treatments.
Where will it file?
Eligible ordinary company filings can go to HMRC, Companies House or both. CICs use a Companies House upload package. Charity and club routes are HMRC-only.
Can you use your existing prepared reports?
Import current-period figures and prior-year comparatives from trial balance, profit and loss or balance sheet exports from Xero, QuickBooks Online or Sage Accounting, or tabular CSV/Excel reports. Review the period and mappings before use. No sign-in to your accounting software is needed.
Can it handle a long accounts period?
Supported accounts periods up to 18 months can produce two CT600 returns. You enter figures once and allocate relevant amounts between the returns.
Can tax dates differ from accounts dates?
Use the supported HMRC-only route for a separate Corporation Tax period. Review the entered tax dates and full accounts attachment.
What if one return has already been filed?
File the remaining short-period CT600 when the first return was already filed with the full accounts, without attaching the accounts again. A separate supported journey amends the first return and files the second as new.
Can you correct a return filed elsewhere?
Supported CT600 amendments include originals filed with another provider. Enter corrected figures and an amendment reason, then review the new filing.
Does it cover your required claims and pages?
Check CT600A loans, associated companies, losses and reliefs against the detailed guides. CT600E has specific charity/CASC routes. Coverage of one box does not mean every treatment is supported.
Can you check the documents before paying?
Start a free preview without card details. Review watermarked drafts, then subscribe when ready to file.
Three examples of choosing the right route
These are fictional prepared figures and dates, not tax advice or a live customer’s filing.
1. Import figures you already have
You have a Xero profit and loss report and a balance sheet for an eligible company. Import the reports one after the other. Review the recognised accounts and any unmapped lines before using them.
- Export the financial reports, rather than bank transactions.
- Upload the first report and review the selected figures and mappings.
- Apply it, then import the second report. Review existing figures before replacing them.
- Check the accounts and tax preview before approving.
You can also import prepared prior-year figures for your accounts comparatives. Check each year’s period and figures, then review both columns in the accounts preview.
Follow the import steps →A QuickBooks Online Excel export or suitable spreadsheet follows the same review principle. You upload exported files. No sign-in to your accounting software is needed.
2. Prepare two CT600 returns for an 18-month period
Your fictional accounts cover 1 January 2025 to 30 June 2026. The displayed returns cover 1 January to 31 December 2025 and 1 January to 30 June 2026. Enter the prepared figures once.
If a qualifying £300 donation was paid in the second return’s period, review the allocation as £0 to the first and £300 to the second. Check the resulting deduction and unused relief in each computation, then review both dated forms and accounts attachments.
Follow the allocation steps →3. File only the outstanding short-period return
Your first CT600 and full accounts have already been filed elsewhere. The remaining return covers 1 January to 30 June 2026. Use the remaining-return journey and enter the figures for that period. It goes to HMRC without attaching the accounts again.
If the first return also needs correcting, use the separate amend-first/file-second journey and review both returns with their full accounts attachment.
File the remaining return →Amend the first and file the second →
Compare the total annual price
Check the billing period, VAT, number of companies, amendments and extra filing fees. Our personal plans are per company, per year, with supported filings and amendments while the subscription is active.
Dormant company annual plan
£10 per company, per year
£8.33 + £1.67 VAT (£10.00 total)
Supported dormant accounts and CT600 filings.
Micro-entity annual plan
£25 per company, per year
£20.83 + £4.17 VAT (£25.00 total)
Supported active micro-entity filings. The separate charity and club routes use their stated scope.
Practice plans cover a pool of companies. New-purchase Practice prices exclude VAT. Separate CIC Companies House upload fees are not included in our subscription. Compare current plans and inclusions →
Who the software suits and who it does not
Supported filing needs
- Eligible ordinary UK micro-entity companies using FRS 105, including property companies, companies limited by guarantee and associated companies.
- Dormant companies using the appropriate dormant route.
- Supported CICs, CASCs, unincorporated clubs and wholly exempt charities, including eligible PTAs, CIOs and SCIOs.
- Customers with prepared figures who want to review and file their own documents.
Choose another service or take advice when needed
- FRS 102, consolidated or audit-required accounts, LLPs or PLCs.
- Group relief, R&D claims or other unsupported supplementary pages and treatments.
- Partly taxable charities, charitable trusts or charity-owned trading subsidiaries in the charity route.
- Bookkeeping, VAT returns or help preparing your underlying figures.
For periods beginning on or after 6 April 2025, the size test uses at least two of three limits: annual turnover no more than £1,000,000, balance sheet total no more than £500,000 and an average of no more than 10 employees. Adjust turnover for the accounts-period length and apply the qualifying-year rules and exclusions. Read the full micro-entity test → Check your organisation route →
Questions about 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.