The application process for mandatory tax adviser registration opened on 18 May 2026. In light of this, HMRC have issued a press release encouraging advisors to check whether they need to register.
From 18 May 2026, a phased rollout begins for tax advisers who interact with HMRC on behalf of clients to Register with HMRC. Advisers will be required to meet minimum standards and there will be ongoing monitoring.
- Registration takes place online and will be rolled out between 18 May 2026 and 31 March 2027.
- A single streamlined digital registration process will replace the previous process and is expected to reduce administrative burdens.
- There is no cost to register.
- Advisers can use HMRC's Online tool to check if they need to register.
The new registration process aims to raise standards in the tax advice market and protect taxpayers from Non-compliant advisors.
- Registration will make it easier for HMRC to identify advisers, ensure consistent standards, and support those who are compliant.
Robert Jones, HMRC's Director for Intermediaries, said, "Tax advisers are encouraged to check guidance now, to understand if and when they need to register, and prepare ahead of their registration window".
The registration process is being rolled out in stages:
- 18 May to 18 August 2026.
- New advisers or advisers who do not already have an Agent Services Account (ASA), Self Assessment online services account or Corporation Tax online services account.
- 18 August to 18 November 2026.
- Advisers without an ASA but with a Self Assessment or Corporation Tax online services account.
- 18 November 2026 to 18 February 2027.
- Advisers who solely provide payroll services.
- 31 December 2026 to 31 March 2027.
- Advisers who have an ASA and financial services organisations. A full definition of this group is expected to be published soon.
- For those who already have an ASA, HMRC will contact them directly via their account if any additional information is required to move them to the new system. They do not need to take any action yet.
Advisers have three months from the start of their window to apply for an ASA. Interaction with HMRC is allowed during this period.
- Those who fail to register by the relevant deadline or do not meet the required standards will not be permitted to interact with HMRC on behalf of clients.
- Where advisers continue to act without registering, sanctions may be applied.
- Failure to register could disrupt individuals and businesses who rely on professionals for tax support.
To register, advisers will need the following information:
- Government Gateway ID and password (one can be created if the adviser does not already have one).
- Unique Tax Reference number for their firm.
- Postcode for the firm.
- Company registration number.
- VAT registration number.
- National Insurance number and date of birth (for sole traders, partnerships and some LLP's).
- The name of their anti-money laundering supervisory body, membership number and renewal date.
HMRC are encouraging advisers to register at the right time to avoid delays and ensure advisers can continue to act without disruption to their clients.
For a practical, step-by-step guide to HMRC's new mandatory agent registration, check out our comprehensive Guide and our upcoming webinar on 'Preparing to Register'.
Useful guides on this topic
Mandatory tax adviser registration with HMRC
From May 2026, all tax advisers who interact with HMRC on behalf of clients will be required to register with them. Who will be required to register? What conditions must be met? What are the consequences of non-compliance with 'mandatory tax adviser registration'?
HMRC's Customer Charter
This is a freeview 'At a glance' guide to HMRC's Customer Charter. HMRC's Charter sets out what taxpayers can expect from HMRC and what HMRC expect from taxpayers. The latest version was issued in November 2020.
Professional Conduct in Relation to Taxation
The Professional Conduct in Relation to Taxation (PCRT) sets out the ethical and professional standards expected of members of the seven authoring professional bodies when advising on UK tax matters.
External links
Tax advisers: check if you need to register under the new rules