Filing Documents With HMRC: What Are Your Obligations?

New guidance issued by HMRC encourages taxpayers to identify areas of uncertainty in their tax returns and to provide additional information unless HMRC agrees otherwise. However, unless the uncertain tax treatment rules apply, this is not legally required and may not always be appropriate.

On 1 September 2025, HMRC released new "promotional material" in four parts which contain guidelines on submitting documents and self-assessment returns to HMRC. This kind of published guidance can be a useful interpretation tool for the taxpayer, clarifying HMRC's views and the approach it is likely to take. It does not, however, override the legal obligations of the taxpayer as established in statute and case law.