Guidance

Self Assessment technical specifications (2026) for trust and estate returns

Use this technical documentation for trust and estate returns if you’re a software developer working with the Self Assessment online service.

From:
HM Revenue & Customs
Published
30 December 2025

Documents

Self Assessment Trust RIM Artefacts version 1.0

ZIP, 1.9 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 different.format@hmrc.gov.uk. Please tell us what format you need. It will help us if you say what assistive technology you use.

Details

Trust and estate returns technical specifications for software developers working with the Self Assessment online service.

Updates to this page

Published 30 December 2025

Sign up for emails or print this page