Knowledge

Self Assessment: What happens if I miss the deadline?

Posted on Feb 1st, 2018 | Tax

The annual deadline for submitting your online Self Assessment and paying any tax owed is midnight on 31st January. While most self-employed people these days choose to file their Self Assessments online, it’s still possible to do so the old way – via paper forms. Be warned though, HMRC must receive this by 31st October.

If you don’t file your return and pay any tax due on time, you’ll face fines – and there are potential extra penalties.

If you’d rather download a guide to read later, check out the jargon-free PDF Self Assessment guide below.

Self Assessment guide banner

How much is the fine if I miss the Self Assessment filing deadline?

Anyone who is required to file a return but misses the deadline receives an automatic £100 fine from HMRC – if you have an online account, this penalty will be added to it.

The fine is imposed regardless of whether you owe tax or not. If you fail to file within three months – that is, by the end of April – HMRC can then impose an additional £10 daily fine for the next 90 days, increasing the total penalty by £900 to £1,000.

Further penalties are imposed after six and then 12 months – and these could be based on the amount of tax you owe if a particularly large sum is outstanding.

On top of these fines, you’ll be charged interest on any unpaid tax.

Can I still submit a Paper Self Assessment?

Should you decide not to submit an online Self Assessment you can file a paper return, although the HMRC deadline for paper submissions is 3 months earlier, 31 October. However, if you miss that, and submit only a paper return after the deadline, the same fine regime applies.

Additional fines for late payment

This may sound obvious, but don’t forget that you must also have paid the tax you owe by the 31st January. If you didn’t pay in time then you’ll face these additional fines:

30 days late 5% of the tax due
6 months late 5% of the tax due at that date
12 months 5% of the tax due at that date

Payment on Account

HMRC runs a system called “payment on account” for those who pay most of their tax through Self Assessment. This can catch many people out, especially if it is their first Self Assessment – as it means that the tax due is often 50% higher than expected. Read more in our article about payment on account.

Can I escape the fine?

HMRC says it will waive the late-filing penalty for people who have a “reasonable excuse”, although this will be done at officials’ discretion.

You may be able to avoid a fine if a close relative died shortly before the Self Assessment deadline, if you have been seriously ill, or even if you have experienced serious IT problems. Fines may also be waived or suspended if you’re unable to file your returns due to issues with HMRC’s online services.

On the other hand, HMRC says it will not waive penalties for those who find the Self Assessment system too difficult to use or who did not receive an official reminder, for example.

If you do wish to appeal against a penalty, you’ll need to fill out what’s called a SA370 form.

What to do next

If you’ve missed the deadline you really need to get on with it as soon as possible. The fines and interest will just keep building up, so you need to file and pay any outstanding tax as soon as possible. If you’re already registered for Self Assessment online, all you need is financial information for the relevant tax year, such as your annual accounts and/or P60, plus details of investment profits, savings interest, pension contributions, etc.

If you aren’t registered yet, you need to start this process right away – but it can take several days, if not weeks, to register as HMRC needs to send you an activation code in the post. You can set the ball rolling by paying HMRC’s website a visit.

Avoiding future problems

Registering for Self Assessment is probably the most awkward part of the process. Once you’re registered, filing returns in future should be far more straightforward, providing you keep a note of your username and password for the service.

Keep any information you’ll need for future returns in a safe place. You should keep your records for at least 22 months after the end of the tax year the tax return is for. So, if you submit your 2017/18 tax return online by 31 January 2019, keep your records until at least the end of January 2020. Also, you should make a note in your diary to file your next return well in advance of next year’s Self Assessment deadline. You can file your return at any time after the current tax year ends on 5th April.

And remember, filing your Self Assessment return early means the size of your next tax bill won’t come as a shock.

We take the pain out of Self Assessments

At Crunch, we’re experts at looking after life’s numbers, so you can trust us to make your Self Assessment as worry-free as it can be. Our expert chartered accountants will take care of you, just like we did for over 7,500 clients in the last tax year.

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