Launch of Phase Two for Tax Adviser Registration
The second phase of the new online registration initiative for tax advisers has officially commenced. This phase particularly targets advisers who hold Self Assessment or Corporation Tax accounts but do not possess an agent services account (ASA). These advisers are required to complete their registration by 18 November 2026.
It is noteworthy that advisers who exclusively provide professional payroll services are exempt from this requirement until 18 November 2026. Additionally, financial services organisations are not obliged to register until 31 December 2026. The introduction of mandatory tax adviser registration is anticipated to enhance customer protection and elevate standards within the tax advisory sector.
Encouragement for Timely Registration
HM Revenue and Customs (HMRC) has urged advisers falling into this second registration window to verify their need for registration and to submit their applications promptly. The first registration phase saw over 4,000 applications submitted and more than 2,000 accounts established, predominantly comprising the smallest group of agents.
The reforms are aimed at fortifying standards in the tax advisory landscape, safeguarding taxpayers, and supporting compliant practitioners. The Modernising and Mandating Tax Adviser Registration (MMTAR) initiative introduces a unified and simplified digital registration system that supersedes a multitude of previous processes, thus facilitating easier interactions for tax advisers with HMRC.
Free and Accessible Registration Process
The registration process is both free and conducted online. It is essential for eligible tax advisers to meet HMRC’s specific registration criteria to apply for an ASA.
Robert Jones, HMRC’s Director of Intermediaries, expressed that these measures collectively aim to bolster trust and transparency within the tax advisory market, thereby supporting high standards and empowering taxpayers to seek advice with increased confidence.
Importance of Compliance and Consequences of Delay
Timely registration will enable advisers to continue providing seamless support to their clients and uphold the trust that individuals and businesses place in professional tax services.
Advisers who did not register during the first window or those newly entering the tax advisory field are encouraged to register without delay. Even if an application is submitted and a registration number is received, advisers are permitted to engage with HMRC while their registration is being processed, with no immediate impact on access to HMRC’s online services.
Failure to register as mandated may result in HMRC restricting an adviser’s ability to act on behalf of clients, with potential enforcement actions and financial penalties for those who persist in operating without fulfilling the registration requirement.
Further Resources on MMTAR
Eligible advisers must adhere to HMRC’s registration conditions in order to apply for an ASA. The government has allocated £36 million towards the enhancement of HMRC’s tax adviser services.
The MMTAR registration opened on 18 May 2026 and is being implemented in phases. The initial registration window concluded on 18 August 2026, and the current window will remain open until 18 November 2026.
Generally, anyone compensated for interacting with HMRC on behalf of another individual concerning their tax affairs is classified as a tax adviser unless exempted. Advisers already possessing an ASA are not required to re-register and will transition to the new digital service by 31 March 2027, receiving direct communication from HMRC if any further information is needed.
Throughout the application processing period, advisers can continue to represent their clients in dealings with HMRC.
The phased schedule for registration is as follows:
- From 18 May to 18 August 2026: Unregistered tax advisers without an ASA interacting with HMRC on behalf of clients.
- From 18 August to 18 November 2026: Advisers with a Self Assessment or Corporation Tax account lacking an ASA.
- From 18 November 2026 to 18 February 2027: Advisers who solely offer professional payroll services.
- From 31 December 2026 to 31 March 2027: Financial services organisations, with a detailed definition for this group already published.