What will filing late actually cost me?
HMRC penalties stack in a way that surprises most people, a return twelve months late with no tax owed still costs £1,600. Put your numbers in and see the real figure.
An estimate based on standard HMRC penalties for 2026/27, rates checked 2026-11-10. It does not cover deliberate or concealed behaviour penalties, which can reach 100% of the tax. If you have had a penalty notice, send it to us and we will tell you whether it is worth appealing.
How HMRC penalties stack up
| How late | Late filing penalty |
|---|---|
| 1 day | £100, automatic, even if you owe nothing |
| 3 months | £10 a day, up to £900 |
| 6 months | £300 or 5% of the tax, whichever is higher |
| 12 months | Another £300 or 5% |
Late payment is charged on top and separately: 5% of the unpaid tax at 30 days, again at six months and again at twelve, plus interest at around 7.25% throughout.
Frequently asked questions
What is the penalty for filing a tax return late?
An automatic £100 the day after the deadline, even if you owe no tax. After three months it becomes £10 a day up to £900, then a further £300 or 5% of the tax due at six months, and the same again at twelve months.
Do I get a penalty if I owe no tax?
Yes. The £100 late filing penalty and the daily penalties apply regardless of whether any tax is owed. Only the six and twelve month percentage-based penalties depend on the tax due.
Are late filing and late payment penalties separate?
Yes, entirely. You can be penalised for both. Late payment penalties are 5% of the unpaid tax at 30 days, six months and twelve months, plus interest running throughout.
Can I appeal a late filing penalty?
Yes, within 30 days, if you have a reasonable excuse: serious illness, bereavement, fire, flood, or an HMRC service failure. Finding the system difficult, not getting a reminder, or not having the money are not accepted.
What if I cannot afford to pay?
Set up a Time to Pay arrangement with HMRC before the deadline rather than after. It stops the late payment penalties, though interest still runs. We can arrange this for you.