Late accounts cost a private company £150 to £1,500, doubled if last year was late too. A CT600 with a filing date on or after 1 April 2026 now costs £200 at one day late and another £200 at three months (was £100). Enter how late you are and see the total both offices will charge.
Who this is for: directors of UK limited companies and LLP designated members. Accounts are due at Companies House 9 months after the year end (6 months for a plc); the CT600 is due at HMRC 12 months after the end of the accounting period. Count a part month as a full month: 1 day to 1 month late = 1.
| Companies House band for one late year | - |
| Companies House late filing penalty | - |
| HMRC penalty for 1 day late | - |
| HMRC penalty for 3 months late | - |
| HMRC tax-geared penalty (10% at 6 months, 20% at 12) | - |
| HMRC CT600 late filing penalties | - |
| Total late filing penalties | - |
| Companies House penalty if filed 1 month later | - |
| HMRC fixed penalties at the old pre-April 2026 rates | - |
| Extra cost from the 1 April 2026 increase | - |
Everything updates as you type. Nothing is uploaded. This runs in your browser.
Full version — $21 once · the saved workbook with the repeat-offence sheet (next year's doubled penalty and the £1,000 third-late CT600 rate), one copy per company and year end.
The saved Excel workbook (6 inputs · 14 formulas): the same 10 lines plus a repeat-offence sheet that shows next year's Companies House penalty if you are late again (the doubling stays) and the CT600 penalties at the £1,000 third-late rate. Keep one copy per company and per year end, change the fig
One payment, one licence key for this tool. The key is shown right after payment.
Companies House 'Late filing penalties' guidance (updated 16 January 2026): private company or LLP £150 (not more than 1 month late), £375 (1-3 months), £750 (3-6 months), £1,500 (more than 6 months); public company £750 / £1,500
Buy the full version — $21I have a keyIt adds up the two late filing penalties a UK company can get for the same year: the Companies House penalty for late accounts, using the statutory bands and the doubling for a second late year, and the HMRC penalties for a late CT600 at the rates for filing dates on or after 1 April 2026, including the 10% and 20% tax-geared penalties.
Directors of UK private limited companies, plcs and LLP designated members who have missed, or are about to miss, the accounts deadline at Companies House or the CT600 deadline at HMRC, and the bookkeepers who file for them. The director is personally responsible for delivering the accounts, so this is the number your company is about to be charged.
Companies House publishes only the accounts bands and HMRC publishes only the CT600 penalties. Neither page adds them up for your own months late, applies the doubling when last year was late too, or shows that a CT600 filed after 1 April 2026 now costs £200 at one day late, where older articles and chatbots still say £100.
The whole calculation on the page is free with no limit on runs: 6 inputs and 10 formulas giving the Companies House penalty, each HMRC penalty, the total, the cost of one more month at Companies House, and how much of the HMRC charge comes from the April 2026 increase. Your figures are computed in your browser and are not sent anywhere.
A saved Excel workbook with 6 inputs and 14 formulas: the same 10 lines as the page plus 4 on a repeat-offence sheet, showing next year's Companies House penalty if you are late again and the HMRC penalties at the £1,000 third-late rate. It is a one-time payment, not a subscription. Keep one copy per company and year end.
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