The UK government seeks feedback on prescribed Corporation Tax formats, mandatory online filing of amended company returns, and proposed timelines for implementation, with the consultation running from 10 March to 2 June 2026.

The UK tax authority, HM Revenue & Customs (HMRC) has initiated a consultation on 10 March 2026 regarding the updates and standardisation of the format of UK corporation tax computations.

The government is introducing prescribed formats for Corporation Tax computations to improve the quality and consistency of Corporation Tax data. This consultation invites feedback on the proposed timeline for moving to this standardised format and the necessary enforcement mechanisms to ensure compliance.

As a related measure, the government will also require mandatory online filing of amendments to company tax returns and seeks views on the timescales for this change and any potential exemptions from this requirement.

The consultation will run for 12 weeks, ending on 2 June 2026.