What penalties are there for filing my self assessment late? You may not be the only one as HMRC estimate they issue around 1 million late safe assessment filing penalties each year!

For Self Assessment there are two types of penalties:

1) Late Filing Penalties

  • A £100 penalty is immediately issued on 1 February (i.e. the day after the filing deadline).
  • This applies even if there is no tax to pay!
  • And this applies regardless of whether you’ve paid the tax by its due date.
  • If the return is more than 3 months late, a daily penalty of £10/day is applied. (For a maximum of 90 days)
  • If the return is more than 6 months late, HMRC penalise you 5% of any tax due or £300 – whichever is larger!

2) Late Payment Penalties

  • HMRC can penalise you 5% of any unpaid tax after 30 days from the due date.
  • This 5% doubles to 10% if any tax is unpaid at 6 months.
  • And this triples to 15% between 6 and 12 months overdue.

What if I can’t afford to pay my tax bill?

You should contact HRMC about difficulty in paying asap!

But HMRC are honestly very supporting and helpful – just explain your situation and they may allow you to set up a payment plan to pay the tax in affordable instalments.Final warning – make sure you stick to the payment plan that is set up. You don’t want to be on the wrong side of HMRC.

I’ve got a penalty but it’s not my fault – now what?

You should appeal this penalty, along with providing details of your reasonable excuse. See more info below…

HMRC may count the following as a reasonable excuse

A reasonable excuse is something that stopped you meeting a tax obligation that you took reasonable care to meet, for example:

  • your partner or another close relative died shortly before the tax return or payment deadline
  • you had an unexpected stay in hospital that prevented you from dealing with your tax affairs
  • you had a serious or life-threatening illness
  • your computer or software failed just before or while you were preparing your online return


  • a fire, flood or theft prevented you from completing your tax return
  • postal delays that you couldn’t have predicted
  • delays related to a disability you have

For the avoidance of any doubt – you must send your return and/or payment as soon as possible after your reasonable excuse is resolved.

What won’t count as a reasonable excuse in HMRC’s eyes

The following won’t be accepted as a reasonable excuse:

  • you relied on someone else to send your return and they didn’t
  • your cheque bounced or payment failed because you didn’t have enough money
  • you found the HMRC online system too difficult to use
  • you didn’t get a reminder from HMRC
  • you made a mistake on your tax return

Lastly there’s very helpful & concise guidance on HMRC’s site about tax appeals and penalties.


Disclaimer: If you are in any doubt about what you can and cannot claim for, it is important that you contact an accountant or relevant tax specialist who can give you bespoke advice directly relevant to your circumstances.
None of the information given here is tax advice.