Deadline generator
Corporation Tax & Companies House deadline calculator
Search your company on the Companies House register and get your Corporation Tax, annual accounts, confirmation statement, VAT, PAYE, CIS and Self Assessment dates for the next 12 months, ready to add to your calendar. Free, no account needed.
How these deadlines are worked out
The calculator starts from the accounts and confirmation statement dates on your company's public record, then applies the standard HMRC and Companies House rules to the details you confirm. Each rule links to the GOV.UK page it comes from.
| Deadline | Rule | Source |
|---|---|---|
| Corporation Tax payment | 9 months and 1 day after the end of the accounting period | GOV.UK: pay Corporation Tax |
| Company Tax Return (CT600) | 12 months after the end of the accounting period | GOV.UK: Company Tax Returns |
| Companies House annual accounts | 9 months after the accounting reference date for a private company; first accounts usually 21 months after incorporation | GOV.UK: annual accounts |
| Confirmation statement | Within 14 days of the end of the 12-month review period | GOV.UK: confirmation statement |
| VAT return and payment | 1 month and 7 days after the end of each VAT period | GOV.UK: VAT payment deadlines |
| PAYE and NIC payment | 22nd of the following tax month if paying electronically (19th by post); quarterly for small employers | GOV.UK: paying HMRC |
| CIS monthly return | 19th of each month, covering the tax month that ended on the 5th | GOV.UK: CIS monthly returns |
| Self Assessment | 31 October for paper returns, 31 January online return and payment, 31 July second payment on account | GOV.UK: Self Assessment deadlines |
Worked example: year end 31 March 2026
A private limited company with an accounting period ending 31 March 2026 that is not paying Corporation Tax by instalments has these dates:
- Companies House accounts
- 31 December 2026
- 9 months after 31 March 2026
- Corporation Tax payment
- 1 January 2027
- 9 months and 1 day after 31 March 2026
- Company Tax Return (CT600)
- 31 March 2027
- 12 months after 31 March 2026
If a deadline falls on a weekend or bank holiday, make sure payments reach HMRC by the last working day before it. Notices from HMRC or Companies House take priority over these rules, especially for first accounts or a changed year end.
Frequently asked questions
When is Corporation Tax due?
Corporation Tax is due 9 months and 1 day after the end of your company's accounting period. The Company Tax Return (CT600) must be filed within 12 months of the end of the accounting period, so the payment comes before the return.
How do I calculate my Corporation Tax due date?
Take your accounting period end date, add 9 months, then add 1 day. For a year end of 31 March 2026 the payment is due by 1 January 2027 and the CT600 by 31 March 2027. Use the calculator above to generate all your dates at once.
When are Companies House accounts due?
A private company normally has 9 months from its accounting reference date to file annual accounts, so a 31 March 2026 year end gives a 31 December 2026 deadline. First accounts are usually due 21 months after incorporation. The exact date is shown on the company's public record, and the calculator uses that date where it is available.
What happens if company accounts are overdue?
Companies House charges an automatic penalty of £150 if private company accounts are not more than 1 month late, rising to £375, £750 and £1,500 for more than 6 months late. The penalty doubles if accounts were also late the previous year.
Do I need an account to use the calculator?
No. Search for your company, confirm the details that are not on the public register (VAT, PAYE, CIS and Self Assessment) and your deadlines are listed straight away. A free account is only needed to save companies to a dashboard.