Modernising and Mandating Agent Registration

Why It Matters

Mandatory registration ties an adviser’s ability to interact with HMRC to its own tax compliance, raising operational risk and creating a powerful enforcement lever for regulators.

Key Takeaways

• Mandatory HMRC agent registration applies to any party assisting tax affairs
• Registration phases start May 18, with staggered deadlines for different agents
• Firms must have no overdue taxes, AML registration, and nominate relevant individuals
• Suspension powers allow HMRC to halt agents for up to 12 months
• Existing agents with an ASA await HMRC contact, but must update details

Summary

The Finance Act 2026 introduces a mandatory agent registration regime, requiring anyone who assists a client’s tax affairs to register with HMRC. The rule applies broadly – from tax advisers to payroll and SDLT agents – and is not limited to those giving formal advice.

Registration is phased: a May 18 start for most agents, with later deadlines for those using online services accounts, third‑party payroll providers and financial services firms. To qualify, firms must have no overdue tax liabilities, hold a current AML registration, and nominate a set of “relevant individuals” who oversee tax‑related decisions. Larger firms must ensure at least five such individuals are identified.

Frank Haines describes the change as “very significant,” noting that HMRC now has powers to temporarily suspend an agent for up to a year on subjective standards. Existing agents with an Agent Services Account (ASA) do not need immediate action, but must keep contact details current and be ready for HMRC outreach.

The rollout forces tax‑service firms to audit their compliance posture, update AML records, and map governance structures. Failure to meet the conditions can trigger suspensions, jeopardising client relationships and revenue streams, while the new digital registration platform promises a streamlined, albeit still evolving, process for both UK and overseas advisers.

Original Description

Finance Act 2026 introduces a package of measures designed to drive up standards in the tax advice market, including mandatory agent registration with HMRC. In this episode, we explain how the process will work and discuss the consequences for advisers of having their registration suspended.

Links 

ICAEW: HMRC’s agent registration guidance lacks key details -  https://www.icaew.com/insights/tax-news/2026/feb-2026/hmrcs-agent-registration-guidance-lacks-key-details

ICAEW: Government reassures agents on registration and sanctions - https://www.icaew.com/insights/tax-news/2026/feb-2026/government-reassures-agents-on-registration-and-sanctions

ICAEW: TAXguide 05/25: Finance Act 2026 - https://www.icaew.com/technical/tax/tax-faculty/taxguides/2025/taxguide-05-25

The HMRC standard for agents - GOV.UK - https://www.gov.uk/government/publications/hmrc-the-standard-for-agents/the-hmrc-standard-for-agents

Host

Stephen Relf, Tax Technical Manager, ICAEW

Guests

Lindsey Wicks, Senior Tax Technical Manager, ICAEW

Frank Haskew, Tax Director, ICAEW

Producer

Ed Adams

Episode recorded: 23 April 2026

Episode published: 13 May 2026