HMRC has published technical specifications for Corporation Tax CT600 RIM artefacts, providing software developers with the requirements needed to build systems compatible with both the CT600 V3 format for 2026 and the earlier V2 format from 2009. These specifications ensure that tax compliance software can accurately process and submit corporation tax returns in line with HMRC requirements. Developers working on tax filing solutions must reference these technical artefacts to maintain compliance with current and upcoming submission standards.
Source: HMRC (GOV.UK) – Read the original