Money Wellness
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calendar icon23 Oct 2023

100 days to go until self-assessment deadline – we answer your FAQs

If you’ve earned untaxed income in the 2022-23 financial year, you have just 100 days left to file your tax return online or face being fined.

The deadline to submit your self assessment online is 31 January 2024. But if it’s done sooner, you have longer to find out what you owe and work out how you’re going to pay.

How do I register for self assessment?

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 Caroline Chell

Caroline Chell

Caroline has worked in financial communications for more than 10 years, writing content on subjects such as pensions, mortgages, loans and credit cards, as well as stockbroking and investment advice.

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