Guidance

Complete your Self Assessment tax return for the last tax year

How to report your income and claim tax reliefs and any repayment due to you using the SA100 tax return, for 6 April 2024 to 5 April 2025.

File online

You can file your tax return online — 97% of people already do it this way.

If you file your tax return online:

  • it’s easier to make amendments and more secure
  • you’ll have an extra 3 months to send it to us
  • you do not have to complete it all at once – you can save your details and finish it later

How to fill in your tax return

Find guidance to help you understand and fill in the sections of your Self Assessment tax return.

You can also use the guidance notes to help you fill in your tax return.

How to fill in your tax return (2025)

Request an accessible format.
If you use assistive technology (such as a screen reader) and need a version of this document in a more accessible format, please email different.format@hmrc.gov.uk. Please tell us what format you need. It will help us if you say what assistive technology you use.

Get supplementary pages

You may need to fill in and send additional forms, known as supplementary pages, along with your SA100 tax return.

There are supplementary forms if you are:

There are also supplementary forms if you need to record:

If you complete a paper tax return

You’ll need to post your tax return to HMRC.

If you live in the UK send to:

Self Assessment
HM Revenue & Customs
BX9 1AS
United Kingdom

If you live outside the UK send to:

HM Revenue & Customs
Benton Park View
Newcastle Upon Tyne
NE98 1ZZ
United Kingdom

HMRC must receive your paper tax return by the deadline.

If you miss the paper filing deadline, send your tax return online instead to avoid a penalty.

SA100 tax return (2025)

Request an accessible format.
If you use assistive technology (such as a screen reader) and need a version of this document in a more accessible format, please email different.format@hmrc.gov.uk. Please tell us what format you need. It will help us if you say what assistive technology you use.

Updates to this page

Published 1 October 2025

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