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Self-assessment tax return

8 articles

The complete guide to filling out your tax return, with explanations of the deadlines and what happens if you submit a late tax return.

Who should submit a tax return?

Last updated: Apr 2019

Find out whether you should submit a tax return, what to do if HMRC sends you a tax return, and what to do if your circumstances change

Self-employed tax return

Last updated: Apr 2019

Find out how what you need to do to file a self-employment tax return - both on paper and online

Self-assessment tax

Last updated: Apr 2019

Find out whether or not you need to fill out HMRC's self-assessment tax return for the 2018-19 tax year. 

Tax returns 2019: important deadlines

Last updated: May 2019

Put these key dates for 2018-19 self-assessment tax returns in your diary to avoid a penalty for missing the deadlines.

Paper tax returns

Last updated: Apr 2019

Find out how to complete paper tax return, plus an explanation of any supplementary pages you might need

Online tax returns

Last updated: Apr 2019

Find out how to make the process of submitting your tax return online as simple as possible. 

Late tax returns and penalties for mistakes

Last updated: Apr 2019

Find out what happens if you file your tax return late, how to get help filling in your tax return, and what penalties you can face for sending HMRC incorrect information

What is a UTR number?

Last updated: Apr 2019

Find out what a unique tax reference (UTR) number is, how you can get one from HMRC and what you'll need to use it for.
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Do your tax return online with Which?
Use our jargon-free calculator to complete and securely submit your tax return direct to HMRC.
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