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Self-assessment tax return

7 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.

How to fill in a self-assessment tax return

Last updated: May 2021

Find out whether or not you need to fill out HMRC's self-assessment tax return for the 2020-21 tax year.

Tax returns 2020: important deadlines

Last updated: Nov 2020

Put these key dates for 2019-20 self-assessment tax returns in your diary to avoid a penalty for missing the deadlines

Online tax returns

Last updated: May 2021

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

What is a UTR number?

Last updated: Apr 2021

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.

Tax returns 2019: important deadlines

Last updated: Oct 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 2021

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

Late tax returns and penalties for mistakes

Last updated: May 2021

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

Work out your tax bill

Use these calculators to estimate how much tax you’ll be paying this year.

National Insurance calculator Income tax calculator Council tax calculator

All 7 calculators