Wenzo guidesWhy are there two dates?
HMRC sets two separate dates for each Corporation Tax accounting period: one for paying the tax and one for filing the Company Tax Return. That means the tax is normally due before the return. Larger companies can have instalment-payment rules instead.
GOV.UK sets out both in its guide to Company Tax Returns.
Do I need to file if there is no tax to pay?
Yes. Once HMRC has sent a notice to deliver a Company Tax Return, you still need to file, even if the company made a loss or has no Corporation Tax to pay.
Is your CT600 due soon?
We prepare your Company Tax Return alongside your annual accounts, and aim to have drafts ready within 24 hours of complete records and answers. From £199, bookkeeping included, paid when you approve.
Find your companyWhat does this look like in practice?
As an illustrative example using the general rules, for an accounting period ending 31 March 2026, the Corporation Tax is usually paid by 1 January 2027 and the Company Tax Return (CT600) is due by 31 March 2027.
If your first accounts are longer than 12 months, the period is split into two tax accounting periods, each with its own return and payment date. Our guide to your first company accounts explains how.
What happens if the CT600 is late?
HMRC publishes a fixed ladder of late filing penalties for the Company Tax Return:
| Time after the deadline | Penalty |
|---|---|
| 1 day | £200 |
| 3 months | Another £200 |
| 6 months | HMRC estimates the Corporation Tax bill and adds 10% of the unpaid tax |
| 12 months | Another 10% of any unpaid tax |
If the return is late 3 times in a row, the £200 penalties rise to £1,000 each.
Paying the tax late is charged interest separately. Companies House late filing penalties for the accounts are a different charge again, and our guide to all company deadlines shows how the dates sit together.
How can Wenzo help?
Our £199 and £499 packages prepare the annual accounts and the CT600 together, with bookkeeping included. You approve both before we file. You can check your own dates with the deadline checker, read about our Corporation Tax return service, or see how much tax is due in our guide to Corporation Tax rates.
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Need help with a deadline?
Call or WhatsApp us for a free, no-obligation chat about your company’s dates and what we need to get your accounts filed.
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