How to appeal an HMRC self assessment penalty

If you’ve received a fine from HMRC, all is not lost: sometimes it can be delayed or reduced.

Why you received a self assessment penalty

Usually one of two things:

How to appeal

You can do it:

  • Online: but only for the £100 late filing penalty.
  • Print and send the SA370 form via post.

In either case, you’ll need to provide a “reasonable excuse”.

What counts as a reasonable excuse

Anything that stopped you from doing your taxes even if you tried to:

  • your partner or relative died right before the tax return deadline
  • you had a serious illness at the time
  • your computer failed as you were filing
  • the HMRC online services didn’t work on that day
  • a fire, flood, theft, or other major incident prevented you.

Basically very serious stuff.

What doesn’t count as a reasonable excuse

A few examples:

  • you asked someone else to do your taxes and they didn’t do it
  • your payment failed
  • you couldn’t figure out how to use HMRC’s website
  • you made an error on your tax return
  • you registered for online filing before the deadline but didn’t get your access code in time.

How much time you have to appeal

You must appeal within 30 days, unless you have a serious reason for appealing late.

If your appeal gets rejected

You can still:

  • appeal to the Finance and Tax Tribunals within 30 days
  • consider alternative dispute resolution.

If you can’t pay the penalty

Then you should:

  • make a “hardship application”
  • appeal to the tribunal: until the appeal is sorted, the payment is delayed.

The important part is: act fast and get help. Our tax accountants are an email away.

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