Filing a Final CT600 When Closing Your Company
Closing a limited company involves two separate processes that need to happen in the right order u2014 the Companies House side (striking the company off) and the HMRC side (a final Corporation Tax return). Get the sequence wrong and you can create real problems for yourself. This guide from Filing Accounts UK explains exactly how to handle your final CT600 when winding down a company.
At Filing Accounts, we help directors close companies correctly, handling both the final accounts and the Companies House side together. For the strike-off process itself, see our guide on how to close a limited company in the UK.
There’s No “Final Return” Flag on a CT600
It’s worth knowing upfront: HMRC doesn’t mark an individual CT600 as “final” in any special way. Instead, HMRC records each return against your company’s UTR and the specific accounting period dates it covers. A CT600 covering a short final period u2014 say, from your last year end to the date you stopped trading u2014 is processed just like any other return, simply for a shorter timeframe.
Get the Sequence Right: CT600 Before DS01
This is the single most important thing to get right. File your final CT600 and accounts before submitting your DS01 strike-off application, not after. If you submit DS01 first and Companies House processes the dissolution before HMRC has recorded your final return, you can end up needing to apply for restoration just to sort out the tax side properly u2014 an entirely avoidable complication.
Is the Company Dormant or Trading at Closure?
This matters more than most directors realise. A company only counts as dormant for HMRC purposes if it had no significant accounting transactions during the period in question. Crucially, this bar is lower than people expect u2014 any business expenditure at all, including something as small as a software subscription, bank charges, or professional fees, means the company is not dormant. In that case, an active CT600 must be filed, even if the actual tax owed comes to nil.
What to Include in a Final CT600
- Trading income and expenses up to the date trading actually stopped
- Any director’s remuneration paid during the final period, if applicable
- A closing balance sheet u2014 for a company with no remaining assets or liabilities, a straightforward £0 net worth position is entered where appropriate
- Any final capital gains or losses arising from disposing of business assets
There’s no minimum value requirement u2014 nil returns and zero balance sheets are handled by HMRC in exactly the same way as any other filing.
Do You Still Need to File Accounts Alongside It?
Yes u2014 as with any CT600, your final tax computations and accounts are generated and filed together in iXBRL format. Filing the accounts at this stage also leaves the public Companies House register tidy and complete right up to closure, which is exactly the right time to sort this out, rather than leaving loose ends.
What if You’ve Already Filed DS01?
If you’ve already submitted DS01 before sorting out your final CT600, you’re in a slightly more complicated position u2014 whether you can still file the return depends on where the strike-off process currently stands. If it hasn’t yet completed, act quickly. If the company has already been dissolved, you may need to look at restoration first; see our guide on what happens if Companies House strikes off your company.
Final CT600 Checklist
| Step | Order |
|---|---|
| Stop trading and settle outstanding business affairs | 1st |
| Prepare and file final CT600 + accounts | 2nd |
| Confirm no outstanding debts remain | 3rd |
| File DS01 to strike off the company | 4th (after CT600 accepted) |
Common Mistakes to Avoid
Filing DS01 Before the Final CT600
This is the single most common and avoidable mistake u2014 always finalise your tax position with HMRC first.
Assuming Minor Costs Count as Dormant
Even small residual costs like bank charges mean the company isn’t dormant for HMRC purposes, and a proper CT600 is still required.
Not Filing Accounts Alongside the Final Return
Your final accounts and CT600 are generated together u2014 leaving one out leaves the public record incomplete right before closure.
Frequently Asked Questions
Should I file my final CT600 before or after DS01?
Before. Filing DS01 first risks Companies House dissolving the company before HMRC has recorded your final return.
Is there a special “final return” box on the CT600?
No. HMRC simply records the return against your UTR and the specific period it covers, which can be a short final period.
Do I need to file if my company only had bank charges left?
Yes. Any business expenditure at all means the company isn’t dormant, so an active CT600 is required, even if the tax owed is nil.
What if I’ve already dissolved the company without filing a final return?
You may need to apply for restoration to correct the company’s tax position u2014 see our guide on restoring a struck-off company.
Closing Your Company? Talk to Filing Accounts UK
At Filing Accounts, we handle final CT600 returns, closing accounts, and DS01 filing together, in the right order, so your company closes cleanly with nothing left unresolved.
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