Important: FilingFriend provides general informational guidance about UK filing requirements. It does not provide tax, accounting, or legal advice. Always confirm requirements with HMRC or Companies House.
The payment deadline arrives first
HMRC's standard rule is that Corporation Tax is due 9 months and 1 day after the end of the accounting period for Corporation Tax. Many small companies assume the return comes first, but the cash deadline usually lands earlier.
The Company Tax Return itself is normally due 12 months after the end of the accounting period.
Work backwards from the payment date
Because payment comes earlier, your bookkeeping, company accounts, and profit estimate need to be ready well before the return filing deadline.
If you use an accountant, agree an internal deadline that gives them enough time to prepare the figures before the tax payment date.
Keep HMRC and Companies House deadlines separate
Annual accounts for Companies House follow one timetable, while Corporation Tax follows HMRC's timetable. They are connected in practice, but they are not the same filing.
Treat them as separate deadlines in your calendar and your task list.
Key deadlines
| Action | Deadline | Why it matters |
|---|---|---|
| Accounting period ends | Varies by company | All Corporation Tax timing flows from the accounting period end date. |
| Pay Corporation Tax | Usually 9 months and 1 day after the accounting period ends | This is the standard HMRC deadline for most small companies. |
| File Company Tax Return | Usually 12 months after the accounting period ends | The filing date is later than the payment date. |
Official references
FAQ
Does the Corporation Tax deadline depend on my year end?
Yes. The deadline is measured from the end of the accounting period, so the exact date depends on your company records.
Do I need to wait until the return is filed before paying tax?
No. HMRC expects payment by the earlier payment deadline even though the full Company Tax Return is usually due later.
Next step
Keep the main dates visible
Use the FilingFriend calendar as a quick reminder layer, then return to this guide when you need the fuller explanation or official source links.