Corporation Tax due date: how to work out yours
Your Corporation Tax due date is 9 months and 1 day after the end of your accounting period. Your Company Tax Return is due 12 months after the end of that period.
Add 9 months and 1 day to your period end for the payment, and 12 months to your period end for the return. The free Corporation Tax deadline tool does the sum from your period end. Check the result against your own accounting period.
The two dates
The payment deadline is 9 months and 1 day after the end of your accounting period.
The filing deadline for the Company Tax Return, the form called the CT600, is 12 months after the end of the accounting period it covers.
They are separate deadlines. GOV.UK says there is a separate deadline to pay your Corporation Tax bill.
So the payment falls due about 3 months before the return.
Worked examples
These are worked out from the two rules above. Check your own date against GOV.UK before you rely on it.
| Accounting period ends | Corporation Tax payment due | Company Tax Return due |
|---|---|---|
| 30 September 2026 | 1 July 2027 | 30 September 2027 |
| 31 December 2026 | 1 October 2027 | 31 December 2027 |
| 31 March 2027 | 1 January 2028 | 31 March 2028 |
If the date falls on a weekend
If the payment deadline falls on a weekend or bank holiday, make sure your payment reaches HMRC on the last working day before it (unless you pay by Faster Payments through online or telephone banking).
In the table above, 1 January 2028 is a Saturday, so that payment should reach HMRC by Friday 31 December 2027 (unless you pay by Faster Payments).
Allow time for the payment to clear
GOV.UK groups payment methods by how fast they clear. Online bank approval, Faster Payments, CHAPS and card payments are same-day or next-day.
Bacs and a Direct Debit you have already set up take 3 working days, and a new Direct Debit takes 5 working days.
You cannot pay Corporation Tax by post.
Large companies
If your taxable profits are above 1.5 million pounds, you must pay Corporation Tax in instalments, and different dates apply. GOV.UK has separate pages for profits between 1.5 million and 20 million pounds and for profits above 20 million pounds.
This post covers the standard single payment.
Do not mix it up with Companies House accounts
Companies House accounts have their own deadline. For a private company they are normally due 9 months from the accounting reference date, which is the date the accounting period ends.
The Corporation Tax payment date and the accounts date can land close together, but they come from different rules and different bodies.
Late filing
GOV.UK says you have to pay a penalty for late filing if you miss the Company Tax Return deadline. The amounts are on a separate GOV.UK page.
How Kofolio counts it down
Each Kofolio company card works out the Corporation Tax payment and return dates from the company's year end, and shows them counted down in days next to the other deadlines.
You can tick a deadline done.
To see every date for a company in one list, type it into the free deadlines tool. The card version lives on the deadlines page.
You can also subscribe to your deadlines as a live calendar feed in Google, Apple or Outlook, so new and changed dates show up on their own. If you want an email too, turn on reminder emails in Settings.
Kofolio files nothing for you. The dates are reminders, not advice, and you stay responsible for your payments and filings.
Frequently asked questions
When is the Corporation Tax payment deadline?
9 months and 1 day after the end of your accounting period.
Is the payment deadline the same as the filing deadline?
No. The Company Tax Return is due 12 months after the end of the accounting period, and the payment is due 9 months and 1 day after it.
Can I pay Corporation Tax by post?
No. GOV.UK says you cannot pay Corporation Tax by post.
What is the CT600?
It is the Company Tax Return form for Corporation Tax.
What happens if I file late?
You have to pay a penalty for late filing. GOV.UK lists the amounts on a separate page.
See your date counted down
Add your company to Kofolio and see its Corporation Tax dates counted down in days. Kofolio is free. Find your company