2026-05-20 ยท MTD News
HMRC publishes 2026 Self Assessment technical specs for software developers
HMRC has published updated technical specifications for individual Self Assessment returns. The documentation is aimed at software developers who build or maintain products that connect with the Self Assessment online service.
If you are a sole trader, landlord, or small business owner, this release is not something you need to act on directly. It is background guidance for the people who write the software you may already use to file your tax returns.
If you use commercial Self Assessment or MTD software, your provider may refer to this documentation when updating their product. There is nothing you need to check or change on your end as a result of this publication.
Source: gov.uk announcement.