Tax Advisers: Secure Your Spot in the Second Registration Window Now Open!

Launch of Second Phase for Online Tax Adviser Registration

The second phase of the online registration initiative for tax advisers has officially commenced, mandating that those with Self Assessment or Corporation Tax accounts, who do not possess an agent services account (ASA), must now register. This new requirement aims to enhance standards within the tax advice sector and safeguard the interests of clients.

It is important to note that advisers who exclusively provide payroll services are exempt from this registration until 18 November 2026, while organisations within the financial services sector will not need to register until 31 December 2026. The introduction of mandatory registration is intended to foster a more trustworthy environment for taxpayers and ensure that only qualified individuals deliver tax advice.

Encouraging Early Registration for Advisers

HM Revenue and Customs (HMRC) is actively urging advisers falling under this second registration phase to evaluate their need for registration and to submit their applications promptly. The first phase saw over 4,000 applications, resulting in the creation of more than 2,000 accounts, indicating a positive response from the smallest agent audience group.

The Modernising and Mandating Tax Adviser Registration (MMTAR) initiative aims to streamline the registration process into a single, user-friendly digital system, thereby simplifying interactions between tax advisers and HMRC. Registration is completely free and can be completed online, with comprehensive guidance and an interactive tool available on the official government website to assist advisers in determining their registration requirements.

Commitment to High Standards in Tax Advice

Robert Jones, HMRC’s Director of Intermediaries, emphasised the necessity of these measures, stating that they will bolster trust and transparency within the tax advice market. He highlighted that these efforts are crucial for maintaining high standards and enabling taxpayers to seek advice with increased confidence.

With the second registration phase now active, it is imperative for advisers within this category to review the guidelines on the government website and ensure registration by the stipulated deadline of 18 November 2026. Timely registration is essential for advisers to continue providing seamless support to their clients whilst preserving the trust that both individuals and businesses place in professional tax services.

Consequences of Non-Compliance

For those advisers who missed the initial registration window or are new to the tax advice field, it is advisable to register without delay. Advisers who submit their applications and receive a registration number will still be permitted to engage with HMRC during the processing of their registration. Access to HMRC’s online services will remain unaffected in the interim.

However, it is crucial to understand that failure to register as required may result in HMRC restricting an adviser’s capacity to act on behalf of clients. Continuing to operate without fulfilling the registration obligation could lead to enforcement actions, including potential financial penalties.

Further Details on MMTAR

Additional information regarding the Modernising and Mandating Tax Adviser Registration (MMTAR) can be found on the government website, where advisers must adhere to HMRC’s conditions to apply for an ASA. The government has allocated £36 million towards the modernisation of HMRC’s tax adviser services.

The MMTAR registration process began on 18 May 2026 and is being rolled out in phases. The initial registration window closed on 18 August 2026, with the current phase running until 18 November 2026. Generally, any individual compensated for interacting with HMRC on behalf of another concerning their tax matters is classified as a tax adviser unless an exemption is applicable.

Existing tax advisers who already hold an ASA are not required to register again; they will be transitioned to the new digital service by 31 March 2027, with HMRC reaching out directly for any further information needed.

The phased rollout timetable is as follows: from 18 May to 18 August 2026, unregistered tax advisers without an ASA; from 18 August to 18 November 2026, advisers with Self Assessment or Corporation Tax accounts lacking an ASA; from 18 November 2026 to 18 February 2027, advisers who solely provide payroll services; and finally, from 31 December 2026 to 31 March 2027, financial services organisations, with a detailed definition for this category having already been published.