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Self-assessment tax return

Who should submit a tax return?

By Ian Robinson

Article 1 of 10

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Who should submit a tax return?

Over nine million people need to complete a self-assessment tax return and submit this to their tax office. 

In this short video, we explain who needs to fill in a tax return and the various options they have for doing so.

If you run your own business, completing a tax return is part and parcel of your financial year. 

But entrepreneurs aren't the only people who are required to complete a self-assessment return. This guides explains when you need to fill out a tax return, and when HMRC will prompt you to complete one. 

And you can get a head start on your 2016-17 tax return with the Which? tax calculator. Tot up your tax bill, get tips on where to save and submit your return direct to HMRC with Which?.

When you need to fill in a tax return

Specifically, you'll need to fill in a tax return if:

  • you're self-employed, a business partner, or director of a limited company
  • you're an employee or pensioner with an annual income of £100,000 or more
  • you have a pre-tax investment income of £10,000 or more
  • you're a 'name' at the Lloyd's of London insurance market
  • you're a minister of religion
  • you're a trustee or representative of someone who has died.

Use the Which? online tax calculator : our easy-to-use and jargon-free tax calculator offers personalised tax tips, and you can submit the form directly to HMRC.

When you’ll usually be sent a tax return

You'll usually also be sent a tax return if:

  • you have untaxed income – from investment, land or property, or from overseas
  • you make capital gains above the annual exempt amount (£11,300 for 2017-18)
  • you were required to fill in a tax return last year
  • you're a pensioner over 65 who gets reduced age-related allowance, though you may be sent a special short version that requires fewer details.

What to do if you get a tax return

Anyone who receives a self-assessment tax return from HMRC is legally obliged to complete and submit it, either by post or by filing a tax return online.

If you miss the deadline and submit a late tax return, you'll be liable to pay a penalty, and may have to pay interest and surcharges on any tax you owe. The deadline for paper tax returns is 31 October; the deadline for online tax returns is 31 January. 

Tax returns if your circumstances change

If your circumstances change and you receive new income during the tax year (you start letting property, for example, or you sell a large number of shares), you must let your tax office know by 5 October following the end of the tax year. It will then decide whether you need to complete a tax return.

Find out more: If you need more help with tax, or any other aspect of your finances, sign up to a £1 trial with Which? and you can get unlimited access to a member of our Money Helpline team to get individual guidance.

  • Last updated: April 2017
  • Updated by: Gareth Shaw

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