Final CT600 when your company has stopped trading

Short version. There’s no “final return” box on the CT600. To stop HMRC expecting returns you do two things: file a final CT600 with the accounting period ending on the date the company stopped trading, and then either tell HMRC the company is dormant, or close it by striking it off at Companies House. Filing the CT600 alone is not enough, because HMRC keeps expecting a return until the company is made dormant or dissolved.

Step 1: File the final CT600 up to the cessation date

A company’s Corporation Tax accounting period normally ends automatically when it permanently stops trading. Your final CT600 should therefore cover the period from the start of the accounting period up to the cessation date.

• Set your accounting period’s end date to the day the company stopped trading (this is often a short period).
• File the CT600 and micro-entity accounts for that period through SimpleCompanyTax as normal.
• Pay any Corporation Tax due by the deadline, which is 9 months and 1 day after the end of that final period.

Note: your final Corporation Tax period may be shorter than your Companies House accounting period. That’s normal and is accepted by HMRC. If your period runs long or splits, see long first accounting period.

Step 2: Tell HMRC the company has stopped trading

This happens in your HMRC online (Business Tax) account, or by phone or letter to the Corporation Tax office quoting your UTR, not on the CT600 and not through SimpleCompanyTax. Which route you take depends on your plans for the company:

• If the company stays incorporated but won’t trade, tell HMRC it is now dormant for Corporation Tax. HMRC then stops issuing a “notice to deliver a Company Tax Return”.
• If you intend to close the company completely, apply to strike it off at Companies House once all Corporation Tax obligations have been met.

What we do vs what you do

Closing a company is a shared job. Here’s the split:

SimpleCompanyTax does:

• Files your CT600 with HMRC.
• Files your micro-entity accounts (if applicable).

You still need to:

• Notify HMRC if the company is becoming dormant.
• Apply for strike-off (DS01) if you’re closing the company.
• Close PAYE and cancel VAT registration if applicable.

What HMRC & Companies House expect

HMRC (Corporation Tax):

• A final CT600 covering the period up to the date you stopped trading.
• Pay any Corporation Tax due, 9 months and 1 day after that period end.
• Tell HMRC the company is dormant or has stopped (this is what stops future returns).
• Close PAYE and cancel VAT registration if you’re registered.
• Keep your records for at least 6 years.

Companies House (closing the company):

• Apply to strike it off with form DS01 (currently £13 online, £18 by post).
• In the last 3 months the company must not have traded, sold stock or changed name.
• It must not be threatened with liquidation and must have no agreements with creditors.
• Tell interested parties within 7 days of applying (members, creditors, employees).
• Distribute any remaining assets first, because anything left passes to the Crown once the company is dissolved.

If the company is insolvent, striking off is not the route. You’d use liquidation through a licensed insolvency practitioner instead. See closing a limited company for the full picture.

So HMRC won’t expect a CT600 again: pick one

• Keeping the company but not trading: tell HMRC it is dormant. HMRC stops expecting returns until it trades again or receives income.
• Closing the company for good: strike it off (DS01). File the final CT600 and pay any tax first. Once it’s dissolved, Companies House tells HMRC and the Corporation Tax record is closed automatically.

Official links

HMRC (GOV.UK)

• Closing a limited company
• Dormant companies and associations
• Corporation Tax: trading and non-trading
• Pay your Corporation Tax bill

Companies House (GOV.UK)

• Strike off your company from the register
• The DS01 strike-off form

Common questions

Do I need to tick a “Final CT600” box?

No. HMRC does not provide a “final return” checkbox on the CT600. A return becomes the last one because it covers the final accounting period and HMRC is separately notified that the company has become dormant or has been dissolved.

Can my Corporation Tax period be different from my Companies House period?

Yes. Your final Corporation Tax period runs to the date you stopped trading, which may be shorter than your Companies House accounting period. This is normal and accepted by HMRC.

Does filing the final CT600 close my company?

No. Filing the CT600 settles your Corporation Tax for the final period. To close the company you also apply to strike it off at Companies House (form DS01). To keep it but pause it, you tell HMRC it is dormant.

Watch out for

• Order matters. File and pay the final CT600 before the company is dissolved, because chasing tax or refunds after strike-off is far harder.
• Expecting a refund? If a Corporation Tax refund is due, it’s generally best to wait until it has been paid before applying to strike off. Once a company is dissolved, money owed to it passes to the Crown and is difficult to reclaim.
• Don’t forget PAYE & VAT. Striking off the company does not cancel these, so close your PAYE scheme and cancel VAT registration separately if you were registered.

Once your Corporation Tax is settled, see paying Corporation Tax after you file for how and when to pay HMRC.