Guidance

Self Assessment technical specifications (2025) for individual returns

Use this technical documentation for individual returns if you're a software developer working with the Self Assessment online service.

From:
HM Revenue & Customs
Published
22 October 2024
Last updated
19 March 2025 鈥� See all updates

Documents

ZIP, 4.81 MB

This file may not be suitable for users of assistive technology.

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 [email protected]. Please tell us what format you need. It will help us if you say what assistive technology you use.

ODT, 552 KB

This file is in an OpenDocument format

This file may not be suitable for users of assistive technology.

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 [email protected]. Please tell us what format you need. It will help us if you say what assistive technology you use.

ODT, 601 KB

This file is in an OpenDocument format

This file may not be suitable for users of assistive technology.

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 [email protected]. Please tell us what format you need. It will help us if you say what assistive technology you use.

ODT, 8.34 KB

This file is in an OpenDocument format

This file may not be suitable for users of assistive technology.

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 [email protected]. Please tell us what format you need. It will help us if you say what assistive technology you use.

3.54 MB

This file may not be suitable for users of assistive technology.

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 [email protected]. Please tell us what format you need. It will help us if you say what assistive technology you use.

3.59 MB

This file may not be suitable for users of assistive technology.

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 [email protected]. Please tell us what format you need. It will help us if you say what assistive technology you use.

ZIP, 23.3 KB

This file may not be suitable for users of assistive technology.

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 [email protected]. Please tell us what format you need. It will help us if you say what assistive technology you use.

ODT, 46.4 KB

This file is in an OpenDocument format

This file may not be suitable for users of assistive technology.

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 [email protected]. Please tell us what format you need. It will help us if you say what assistive technology you use.

ODT, 36.6 KB

This file is in an OpenDocument format

This file may not be suitable for users of assistive technology.

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 [email protected]. Please tell us what format you need. It will help us if you say what assistive technology you use.

Details

You should use this technical documentation for individual returns if you鈥檙e a software developer working with the Self Assessment online service.

Updates to this page

Published 22 October 2024
Last updated 19 March 2025 show all updates

  1. The attachments 'MTR Mapping version 1.1', 'Special cases version 0.1a' and 'Exclusion cases version 0.1a' have been added. The attachments 'Calculate Tax and NIC MTR version 2.4.0a', 'Calculate Tax and NIC MTR version 2.4.1a 鈥� Annex C', 'Test Case generator (Tester) MTR version 2.4.0' and 'Test Case Generator (Tester) MTR version 2.4.1' have been updated.

  2. The attachments 'Calculate Tax and NIC MTR version 2.3.0a' and 'Test Case generator (Tester) MTR version version 2.3.0' has been added.

  3. The attachments 'Calculate Tax and NIC MTR version 2.3.1a', 'Payments on Account (Stage 13) Tax and NIC calculation version 1.0.0a' and 'Test Case Generator (Tester) MTR version 1.3.0' have been added.

  4. First published.

Sign up for emails or print this page

Related content