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Every year almost 1 million people miss the tax filing deadline and have to pay tax return penalties.
There are three different kinds of tax return penalties:
Total fines for filing a year late start at £1,600 but can technically be unlimited – it all depends on how large your original tax bill was:
| How late you are | Fine (each gets added to the others!) |
|---|---|
| between 1 day and 3 months | £100 flat fine |
| between 3 months and 6 months | £10 each day |
| between 6 months and 12 months | £300 flat or 5% of your tax bill (whichever is greater) |
| over 12 months | £300 flat or 5% of your tax bill (whichever is greater) |
If you owe a tax bill and miss the payment deadline you will have to pay additional fines:
| How late you are | Late payment penalty |
|---|---|
| between 1 day and 30 days | 0 |
| between 30 days and 6 months | 5% of your tax bill |
| between 6 months and 12 months | another 5% |
| over 12 months | and another 5% |
This is calculated yearly, and it is (how else) added to your other penalties as well.
As of April 7 2025, the Bank of England’s interest rate is 👉 4.5%.
Or see our Guides, Calculators or Taxopedia