Money Wellness
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calendar icon02 Oct 2023

Self-assessment registration deadline looming – we answer your FAQs

If you’ve earned untaxed income in the 2022-23 financial year and you haven’t completed a tax return before, you need to register to use the self-assessment system by this Thursday (5 October).

What happens if I miss the deadline?

There’s no penalty for missing the deadline. But you could be fined if you leave it so long that you end up submitting your tax return or paying your bill late.

How do I register?

You’ll find everything you need to know in HMRC’s guide to registering for self assessment.

It’s best to register as soon as possible because you’ll have to wait to be sent your unique taxpayer reference (UTR) number before you can start your tax return. This can take up to 10 working days in the UK and up to 21 working days if you’re abroad.

Once you have your UTR number, you can sign up for self assessment online. You’ll then be sent a letter with an activation code. This can take up to seven working days in the UK and up to 21 working days if you’re abroad.

The code will allow you to finish the sign-in process. You will then be able to submit your tax return.

What’s the deadline for submitting my tax return?

31 October – you need to get paper returns to HMRC by the end of October.

31 January – you need to get online returns to HMRC by the end of January. You also need to pay your bill by this date, including the first payment on account if you’re self employed.

Can I claim for business expenses?

Yes. You may be able to reduce the amount you have to pay in tax by claiming for certain business expenses, including:

  • office stationery
  • business trips
  • the cost of running business premises (if your workplace is your home, you may be able to claim for some of your bills)

What are the penalties for missing the submission deadline?

If you miss the deadline for submitting your tax return online, you may be fined £100. After three months, this goes up to £10 a day for up to 90 days. If your return is more than six months late, you’ll be fined even more. And this increases again after 12 months.

What are the penalties for missing the payment deadline?

You’ll be charged daily interest from the date the payment was due. The interest rate is currently 7.75%. There may be further penalties if you miss the deadline by a few months.

What should I do if I’m going to miss the payment deadline?

Speak to HMRC. They may be able to set up a time to pay arrangement. This lets you pay in smaller chunks over an agreed period. You’ll still be charged interest on anything you pay after the deadline, but it’ll be at a lower rate than the standard late-payment rate.

Avatar of Rebecca Routledge

Rebecca Routledge

A qualified journalist for over 15 years with a background in financial services. Rebecca is Money Wellness’s consumer champion, helping you improve your financial wellbeing by providing information on everything from income maximisation to budgeting and saving tips.

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