HMRC to Introduce New SDLT Submission Requirements from May 2026

HMRC is set to introduce significant regulatory changes affecting Stamp Duty Land Tax (SDLT) submissions from May 2026. These changes form part of the Government’s commitment, announced in the Autumn 2025 Budget, to modernise and strengthen oversight within the tax‑advice market.

Under the forthcoming Finance Bill 2025-2026, anyone who interacts with HMRC on behalf of clients will be required to register as a tax adviser and meet new minimum standards. This applies to a wide range of activities, including submitting tax returns, sending documents to HMRC and communicating by phone, email or online portal.

HMRC has confirmed that SDLT submissions fall within the new regime. Filing an SDLT return is now categorised as tax advice for the purposes of registration, even where the professional involved does not provide wider tax guidance. As a result, professionals responsible for submitting SDLT returns will be brought within the scope of these new requirements. 

A transitional period of at least three months will accompany the May 2026 start date to allow organisations time to implement the changes. HMRC indicated that further practical guidance would be published in January 2026, though this has not yet been released.

Some aspects of the new rules still require clarification, including whether registration will be required at an individual level, firm level, or both. Industry bodies have raised questions regarding the breadth of the definitions used and how these will operate in practice. Further information from HMRC is expected in due course.

These changes represent a shift in how HMRC regulates those acting on behalf of clients, particularly within property transactions. Clients may see updates to the administrative processes surrounding SDLT once final guidance is issued. We will continue to monitor HMRC updates and will keep our clients informed as further details become available. If you have any questions about how these changes may affect your transaction, our team is here to help.