Late Filing Penalty Calculator
Enter your accounting period and when you filed, or leave the dates blank if you have not, to see the Companies House and HMRC penalties and when they next rise.
Accounting period
How the penalties build up
| Charged by | For | Penalty |
|---|---|---|
| Companies House | Accounts 1 to 3 months late | 375.00 |
| HMRC | Company Tax Return filed late | 100.00 |
| Total | 475.00 |
Example. A private company with a 31 March 2025 year end that files its accounts on 14 February 2026, 45 days late, and its Company Tax Return on 14 April 2026, 14 days late, is charged £375 by Companies House and £100 by HMRC: £475 in all.
Companies House penalties
Companies House charges a single penalty set by how late the accounts arrive, and it is charged automatically, even if the accounts are one day late or the company is dormant. The penalty is doubled if the previous year's accounts were late as well.
HMRC penalties
HMRC charges a flat penalty when a Company Tax Return is one day late and the same again at three months. At six months it adds 10% of the unpaid Corporation Tax, and another 10% at twelve months. The flat penalties are five times higher when the two returns before were late too. They apply even when there is no tax to pay.
The April 2026 increase
HMRC's flat penalties doubled for returns with a filing date on or after 1 April 2026: from £100 to £200, and from £500 to £1,000 for a third late return in a row.
Two separate deadlines
The accounts are due at Companies House nine months after the year end and the Company Tax Return is due at HMRC twelve months after it. Missing one does not affect the other, and each body charges its own penalty.
Appeals and interest
Both penalties can be appealed, but only where something outside the company's control stopped it filing on time. Interest on Corporation Tax paid late is charged separately and is not a penalty.
Companies House penalties for late accounts
Doubled if the accounts for the previous financial year were late as well.
| Time after the deadline | Private company | Public company |
|---|---|---|
| Up to 1 month | £150 | £750 |
| 1 to 3 months | £375 | £1,500 |
| 3 to 6 months | £750 | £3,000 |
| More than 6 months | £1,500 | £7,500 |
HMRC penalties for a late Company Tax Return
The flat penalties are charged on each return. The higher amounts apply to returns with a filing date on or after 1 April 2026.
| Time after the deadline | Due on or after 1 April 2026 | Third late return in a row | Due before 1 April 2026 |
|---|---|---|---|
| 1 day | £200 | £1,000 | £100 |
| 3 months | Another £200 | Another £1,000 | Another £100 |
| 6 months | 10% of the unpaid tax | 10% of the unpaid tax | 10% of the unpaid tax |
| 12 months | Another 10% of the unpaid tax | Another 10% of the unpaid tax | Another 10% of the unpaid tax |
Frequently asked questions
How much is the penalty for filing company accounts late?
For a private company: £150 up to 1 month late, £375 1 to 3 months late, £750 3 to 6 months late, £1,500 more than 6 months late.
How much is the penalty for a late CT600?
£200 when the return is one day late and another £200 at three months, for returns due on or after 1 April 2026. At six months HMRC adds 10% of the unpaid tax, and the same again at twelve months.
Does a dormant company get a late filing penalty?
Yes. Companies House charges the same penalty for late dormant accounts as for any others, and HMRC charges its flat penalties on a late return even when no tax is due.
Is the Companies House penalty doubled for a second late year?
Yes. If the accounts for the previous financial year were also filed late, the penalty is doubled.
Can I appeal a late filing penalty?
Yes, but an appeal only succeeds where something outside the company's control prevented filing on time. Not knowing the deadline, or an accountant's delay, is not normally accepted.
Related calculators
Sources: Penalties for late filing of accounts, Penalties for late filing of a Company Tax Return on GOV.UK.
Last updated .
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