self-Assessment penalties

self-assessment penalties

Whether you are liable to pay any tax or not but received a notice to deliver a self-assessment tax return, you are obliged to do so. Not adhering to the self-assessment deadlines means you will receive self-assessment penalties. Find out what exactly happens if you file your self-assessment late and what penalties you can expect.

How much is the fine for late self-Assessment?

Self-assessment penalties depend on how long behind you are with your tax return.  You can receive a penalty for both not submitting your self-assessment and not paying the tax due. If you are in a partnership, all partners can receive a penalty if your partnership tax return is late.

Self-assessment penalties for late filing

Timeframe Penalty
1 day
3 months late
£10 for each additional day for up to 90 days (£900 max). This is additionally to £100 penalty above.
6 months late
£300 or 5% of the tax due whichever is higher. This is additionally to £100 penalty above.
12 months late
Additional £300 or 5% of the tax due whichever is higher. This is additionally to £100 penalty above.

If you don’t pay your self-assessment bill before the deadline, HMRC will start charging interest from the date your payment was due. The interest rates can change, so it’s best to check this directly on HMRC website.

Self-assessment penalties for late payments

Timeframe Penalty
30 days late
5% of the tax due
6 months late
Another 5% of the tax due
12 months late
Another 5% of the tax due

Can you appeal against self-Assessment penalties?

You can appeal against self-assessment penalties only if you have a reasonable excuse. You also have to submit your tax return.

What can count as a reasonable excuse?

A reasonable excuse means that you were trying your best to submit your tax return and pay your tax on time but because of some unexpected events in your life you were unable to meet the deadlines. The reasonable excuse can be:

  • Serious illness
  • Serious accident
  • Death in your family
  • Problems with software
  • Problems with HMRC website if you file online
  • Fire
  • Postal delays

What is the penalty for filing an incorrect tax return?

If you were careful when preparing your self-assessment tax return and made a genuine mistake, you won’t receive a penalty. But you have to admit to your mistake and correct it as soon as you realise you made it.

If you made a mistake on your self-assessment due to being careless, you can face a penalty of even 30% of the extra tax you owe. If you deliberately included the wrong information in your tax return to reduce your tax bill, the penalty could range from 20% to 70%. If your incorrect tax return was submitted deliberately and you hid it form the authorities, the penalty for this can reach even 100%.

In general, the longer you stay quiet about the mistake on your self-assessment, the higher the penalties can be.

Need help with your self-assessment tax return? Contact our accountants in Oxford.

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