What Happens if You Miss the Self Assessment Deadline?

Have you missed the self-assessment deadline? Well, you’re not alone! HMRC said that over 958,00 taxpayers missed the self-assessment deadline on 31 January 2020. That’s nearly 10% of UK taxpayers who needed to file a tax return! Here’s what happens if you’ve missed the deadline.

Updated 29 September 2021

1. What Happens If You Miss the Self-Assessment Deadline?

You need to file your tax return online for the previous tax year by 31 January each year – so your return for the tax year 2020/2021 is due by 31 January 2022.

If you miss this deadline you will receive an automatic £100 fine from HMRC. This late filing penalty is imposed regardless of whether you owe tax or not, it is for failing to put in the SA100 tax return form (which you’ll find when you signed into your .GOV account with your HMRC user ID). That means even if your business activities have not resulted in a profit, you must still meet complete a tax return.

Failure to file your tax return within the following 3 months (the end of April) could result in an additional £10 a day fine for 90 days, bringing the total penalty to £900. Additional penalties are then imposed after 6 and 12 month periods (which may be based on the amount of tax owed). You should also expect to be charged interest on any unpaid tax.

Read the full guide to Self Assessment Tax Return Penalties

.

2. Can I Appeal the £100 HMRC fine?

You can appeal a late payment penalty. HMRC says it will not impose the late filing penalty for people who have a “reasonable excuse”. This means that, in some cases, they will reverse the penalty. Typical reasons fines will typically be waived or suspended if HMRC’s online services pages have not been working though. However, HMRC will not cancel penalties for those who found the self-assessment online system difficult to use, didn’t understand the form or did not receive the automated official reminder.

Read this guide to find out how to appeal an HMRC self-assessment penalty and the form you’ll need to use.

3. What Happens if You Miss the Self-Assessment Registration Deadline?

The deadline to register as self-employed is the 5th October following the end of the tax year you started working for yourself. If you miss the self-assessment registration deadline you can face a £100 penalty or further fines of up to 30% of any tax you should have paid.

Related:

About Anita Forrest

Anita Forrest is a Chartered Accountant, spreadsheet geek, money nerd and creator of www.goselfemployed.co - the UK small business finance blog for the self-employed community. Here she shares simple, straight-forward guides to make self-employment topics like taxes, bookkeeping and banking easy to understand.