HMRC 'mandatory requirement' alert as new rules start Monday May 18 for some

HM Revenue and Customs (HMRC) has issued an alert today (May 14) as new rules will commence on Monday, May 18. People affected by the upcoming 'mandatory' requirements are being made aware in advance. The changes are hoped to "raise standards in the tax advice market and protect taxpayers ". From the start of next week, a new registration requirement for tax advisers will roll out. HMRC says the new mandatory tax adviser registration requirements will "protect customers and raise standards in tax advice ". Online registration will roll out in stages between May 18, 2026, and March 31, 2027. Registration is free, and step-by-step guidance is available on GOV.UK to help advisers understand what they need to do and when. A new registration requirement for tax advisers, who are paid to interact with HMRC on behalf of clients, rolls out online from next week. HMRC says: "A single, streamlined digital registration system will replace a range of previous processes and reduce unnecessary administrative burdens on advisers. Advisers can also use a new interactive checker tool on GOV.UK to quickly determine whether they need to register and what to do next." GOV.UK guidance about Modernising and Mandating Tax Adviser Registration (MMTAR) was published earlier this year. Eligible tax advisers must meet HMRC’s registration conditions to apply for an agent services account (ASA). MMTAR was first announced at Budget 2025, following public consultation in 2024, as "part of wider action to raise standards in the tax advice market and protect taxpayers". Consultation respondents were strongly in favour of tax adviser registration, which HMRC says "will help identify advisers more easily, ensure consistent standards, and support those who play by the rules." Robert Jones, HMRC’s Director for Intermediaries, said: "Tax advisers are encouraged to check the guidance now, to understand if and when they need to register, and prepare ahead of their registration window. We are taking action to raise standards in the tax advice market, support economic growth and help close the tax gap. "These new registration requirements will create a fairer market for taxpayers, help them get more reliable advice, and support the majority of advisers who play by the rules." It will be introduced gradually, with different groups invited to register at different stages: May 18, to August 18, 2026 New tax advisers, or advisers interacting with HMRC without an ASA, Self Assessment or Corporation Tax account. August 18 to November 18, 2026 Advisers with a Self Assessment or Corporation Tax account, but without an ASA. November 18, 2026 to February 18, 2027 Advisers who solely provide payroll services. December 31, 2026 to March 31, 2027 Those who already have an ASA, and Financial services organisations. A full definition for this group will be published soon via secondary legislation. Advisers will have three months from the start of their registration window to apply for an ASA. They can continue to interact with HMRC on behalf of their clients: during these three months while HMRC considers their registration. A statement on GOV.UK reads: "Registration is free, and step-by-step guidance is available on GOV.UK to help advisers understand what they need to do and when. If a tax adviser already has an ASA, they do not need to register again. HMRC will contact them through their ASA if any additional information is needed to move them to the new digital system. "Applying at the right time will help avoid delays and ensure advisers can continue supporting their clients without disruption. Eligible advisers who do not register by the relevant deadline, or who fail to meet the required standards, will not be permitted to interact with HMRC on behalf of clients. "Where advisers continue to act without registering, HMRC may apply sanctions, including financial penalties if they continue to interact with HMRC when told to stop. Failing to register could also delay or disrupt services for clients and damage trust with individuals and businesses relying on professional tax support."