Tax returns Who should submit a tax return?

filling in tax

If you’re self-employed, you'll need to fill out a tax return

Over nine million people need to complete a self-assessment tax return (SA100 or SA200) and submit this to their tax office. 

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

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.

Go further: 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 speak to a member of our Money Helpline team to get individual guidance.

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 (£11,100 for 2015-16);
  • 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 which 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 don't 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.

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