Late tax return penalty calculator.
See roughly what HMRC could charge for a late Self Assessment return and late payment.
Estimate your penalties
Enter how late you are and how much tax is unpaid.
How penalties build up
The late filing penalty is £100, then £10 a day after three months up to £900, then the greater of 5% of the tax due or £300 at six months and again at twelve months.
Late payment adds 5% of the unpaid tax after 30 days, six months and twelve months, plus interest.
About this calculator
What the late tax return penalty calculator does
This calculator estimates the penalties and interest HMRC may charge if you file your Self Assessment tax return late or pay your tax late. Enter how late you are and how much tax is unpaid to see the likely total.
Quick answer
There is a £100 penalty the day after the filing deadline, even if you owe nothing. After that the penalties build up over three, six and twelve months, and late payment charges apply on top.
How HMRC late filing penalties work
| When | Late filing penalty |
|---|---|
| 1 day late | £100 fixed penalty |
| 3 months late | £10 per day for up to 90 days, maximum £900 |
| 6 months late | Greater of 5% of the tax due or £300 |
| 12 months late | Another 5% of the tax due or £300, whichever is higher |
Late payment penalties and interest
| When | Late payment charge |
|---|---|
| 30 days after the due date | 5% of the tax unpaid |
| 6 months | A further 5% of the tax unpaid |
| 12 months | A further 5% of the tax unpaid |
| Throughout | Interest on the unpaid tax from the due date |
Worked examples on £3,000 unpaid tax
| Position | Approximate penalties |
|---|---|
| 1 day late | £100 |
| 40 days late | £250 |
| About 4 months late | £550 |
| 7 months late | £1,600 |
| 13 months late | £2,050 |
These totals exclude interest and are approximate. Interest is added daily at the HMRC rate.
Can I appeal a penalty?
Yes. HMRC accepts a reasonable excuse such as serious illness, a bereavement, or a failure of its own online service. You have 30 days from the date of the penalty notice to appeal. If you were never required to file, or you filed on time and HMRC lost the return, tell them as soon as possible.
What to do if you are already late
- File the return as soon as you can, because daily penalties stop once it is filed.
- Pay what you owe, or set up a Time to Pay arrangement with HMRC.
- Appeal if you have a reasonable excuse.
- Ask our accountants to prepare and file the late return for you.
Frequently asked questions
What is the penalty for filing a tax return one day late?
An automatic £100 penalty, even if you owe no tax.
How long before the penalties stop?
The daily £10 penalties stop after 90 days, but the six and twelve month penalties and the late payment charges continue to apply.
Will HMRC cancel my penalty?
Only if you have a reasonable excuse that HMRC accepts, or it was issued in error. It is worth appealing if you think either applies.
Authorised and regulated
Is Cheap Tax Returns authorised and regulated? Yes.
Your return is prepared by qualified UK accountants holding qualifications from the leading accountancy bodies: ICAEW, ACCA and AAT. We are also on the ICAEW approved employers list, so you can file with confidence.
Regulated by the professional bodies. Reviewed by qualified accountants. Part of Accotax.
Questions, answered.
You can appeal if you had a reasonable excuse. File as soon as you can, as penalties keep growing until you do.
Yes. See our late tax return service for a fixed fee.
Know your price before we start.
- Fixed fee confirmed in writing before any work begins
- ICAEW, ACCA and AAT-qualified accountants
- Filed with HMRC and confirmed, so you have proof
- A real person on the phone: 0203 4411 258