MTAR10800 - Scope and requirement to register: when tax advisers must register and transitional arrangements
Overview
All tax advisers who interact with HMRC on behalf of another person’s tax affairs must register with HMRC, unless a specific exception applies. For a list of exceptions, see MTAR10300.
Registration is being introduced in tranches, with each tranche having a three-month window in which to register. The registration window for each tax adviser business will depend on their current registration status with HMRC, and some businesses have been given more time before they must register.
When tax advisers must register
| Period | Type of tax advisers |
|---|---|
| 18 May to 18 August 2026 | New tax advisers, or those interacting with HMRC without an agent services account (ASA), Self Assessment or Corporation Tax account. |
| 18 August to 18 November 2026 | Tax advisers with a Self Assessment or Corporation Tax account, but without an ASA. |
| 18 November 2026 to 18 February 2027 | Advisers who solely provide payroll services and who don’t have an ASA. |
| 31 December 2026 to 31 March 2027 | Financial services organisations without an ASA. |
HMRC has published an interactive guidance tool on GOV.UK to help businesses to work out which tranche they fall into.
Businesses will have three months from the start of their registration window to apply for an agent services account (ASA). During this period, they can continue to interact with HMRC on behalf of their clients. Businesses can also continue to act for clients and interact with HMRC while their registration is being processed (if they have registered during their appropriate registration window).
Interaction with other services
Businesses should be treated as part of the payroll or financial services tranche only where they solely provide those services. If a business also provides other services that brings it within scope of earlier tranches (for example, tax or accountancy services involving interaction with HMRC), it will be required to register in line with the relevant earlier tranche.
Businesses must consider whether they undertake any wider activities that might bring them within scope of earlier registration requirements.