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Tax return deadline: Could an error cost you?

One in five admit to tax return mistakes

Our survey shows that many people are worried they have overpaid tax because they don’t understand the rules

One in five (19%) people who complete self-assessment tax returns think they may have overpaid a tax bill, either because they made a mistake on their tax return, or they didn’t understand their paperwork, according to new research from Which?.

This comes as the deadline for completing a tax return online fast approaches, on 31 January 2017. With more than 10 million people completing a tax return in 2015, our findings suggest large numbers of British taxpayers could be losing out on claiming valuable allowances.

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.

Property income most taxing

Tax rules for property income confuse people more than any other area of the tax system, with a third (34%) of people who declared property income saying the struggled.

Taxes on dividends and rules around pensions relief also create a headache for many taxpayers, with 32% and 31% of taxpayers reporting difficulties in these areas.

Who needs to complete a tax return?

If you are self-employed, a company director, a minister of religion or have an income of over £100,000 you will need to complete a self-assessment return ahead of the 31 January deadline. You may also need to complete a return if:

  • You have received investment income worth more than £10,000
  • You received more than £2,500 untaxed income (if less, you may be able to settle your tax bill over the phone)
  • You or your partner earned more than £50,000 and one of you claimed child benefit
  • You lived abroad and earned a UK income, or vice versa

What to do if you still need to file your tax return

Register with HMRC

In order to complete your tax return online, HMRC needs to issue you with a Unique Taxpayer Reference (UTR) number. This must be done well before the 31st January deadline, as it can take up to 10 working days to arrive.

Find out more: What is a UTR number? – read our in-depth guide

Get to grips with allowances and expenses

If you’re self-employed, there are a whole host of business expenses you can claim for to lower your tax bill. Not all of your expenditure can be used, however, so it’s worth quickly getting up to speed with what you can and can’t claim for.

Find out more: Tax allowances and expenses – what you can write off your tax bill

Use the Which? online tax calculator

Which? has partnered with SimpleTax to help you fill out your tax return fuss-free. Our calculator cuts through the complex tax jargon to help you complete your return, and offers helpful hints and tips about where you can make savings. You can also submit your return directly to HMRC via the calculator.

Find out more: The Which? online tax calculator – explore our powerful new tool

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