
Tax advisers have one month left to register under new mandatory requirements designed to raise standards in the tax advice market.
HM Revenue and Customs (HMRC) is encouraging anyone who has not yet registered to check if they need to and submit their application as soon as possible.
The first phase of Modernising and Mandating Tax Adviser Registration (MMTAR) closes on 18 August 2026 for new tax advisers, or advisers interacting with HMRC without an agent services account (ASA), Self Assessment or Corporation Tax account.
MMTAR is a single, streamlined digital registration system that is replacing a range of previous processes, making it easier for tax advisers to interact with HMRC.
Registration is free and online. Step-by-step guidance and an interactive checker tool are available on GOV.UK to help advisers understand if they need to register and what action they must take.
Eligible tax advisers must meet HMRC's registration conditions to apply for an ASA.
Robert Jones, HMRC's Director of Intermediaries, said:
“These new requirements will help create a fairer, more transparent tax advice market, support those advisers who meet high standards, and give taxpayers greater confidence in the advice they receive.
“And with one month to go until the first registration deadline, tax advisers who have not yet registered should act now and check the guidance on GOV.UK.”
Tax advisers who miss their relevant registration deadline may face restrictions on their ability to interact with HMRC on behalf of clients. Where advisers continue acting without registering when instructed to stop, HMRC may apply sanctions including financial penalties.













