The UK’s new mandatory disclosure rules which took effect from 28 March 2023 require arrangements caught by the rules and entered into on or after this date to be reported to HMRC. Since 1 June 2023, reportable arrangements should be notified to HMRC via the Mandatory Disclosure Rules service.
Taxpayers and agents were still able to use the DAC6 service until 31 May 2023 to tell HMRC about arrangements reportable before 28 March 2023, or to send additional information, replacements or deletions for previously submitted disclosures.