Tax advisers: one month left to register under new rules (HM Revenue & Customs, 20 July 2026) →
The four-phase timetable also brings financial services organisations into the same regime from 31 December 2026. By 31 March 2027 both the accountant and the financial planner sitting around a business owner will have been through the same HMRC registration.
What Modernising and Mandating Tax Adviser Registration is
The regime was announced at Budget 2025 after a public consultation in 2024. HMRC published its guidance on 17 February 2026 and opened the online service on 18 May 2026. Registration is free, done online, and replaces several earlier processes with a single route into an agent services account. The government is putting £36 million into the modernisation as part of its Plan for Growth (HMRC, 20 July 2026).
HMRC has published four phases:
- 18 May to 18 August 2026
new tax advisers, or advisers interacting with HMRC without an agent services account, Self Assessment or Corporation Tax account.
- 18 August to 18 November 2026
advisers with a Self Assessment or Corporation Tax account, but without an agent services account.
- 18 November 2026 to 18 February 2027
advisers who solely provide payroll services.
- 31 December 2026 to 31 March 2027
those who already have an agent services account, and financial services organisations.
Each group has three months from the opening of its window to apply, and a firm can carry on acting for clients during those three months and while its registration is considered. Robert Jones, HMRC's Director of Intermediaries, said the purpose is a fairer, more transparent tax advice market and greater confidence for taxpayers in the advice they receive.
If your practice has held an agent services account for years, HMRC's guidance says you do not need to register again at this stage. HMRC will contact you through the account if it needs more information.
Which legal entities are in phase one
Phase one covers any legal entity that interacts with HMRC for paying clients without already holding an agent services account, Self Assessment or Corporation Tax agent code. HMRC's guidance states that it is the legal entity that registers, and individual employees do not.
Illustration using a made-up practice group. The main trading company has held an agent services account since 2019. Eighteen months ago the partners incorporated a second company for a specialist R&D and capital allowances team, and this spring they moved bookkeeping and payroll into a third. Under the published timetable the three entities can sit in three windows: the original company from 31 December 2026; the specialist company in phase one, closing 18 August 2026, if it has dealt with HMRC in its own name without its own account; and the payroll company from 18 November 2026 if payroll for clients is all it does.
Firms that have restructured, incorporated an LLP or created a subsidiary for a service line in the past two years may have an entity in phase one while the parent's account covers only the parent. HMRC publishes an interactive checker for this question.
HMRC treats you as a tax adviser if you interact with HMRC about someone else's tax affairs and are paid for it. Interaction includes phone, post, email, messages through the GOV.UK website or HMRC app, making payments, and sending returns, claims or other documents. Registration is required even if you do not describe yourself as a tax adviser, even if you are a registered sole trader, even if tax is not your main business, and even if you act for one client.
The conditions your firm has to meet
HMRC's registration conditions require evidence that the business is supervised for anti-money laundering, as a digital copy of the supervision certificate or a confirmation email. The business must not have relevant outstanding tax returns or unpaid tax unless covered by a payment plan; must not be subject to an HMRC decision refusing to interact with it, an anti-avoidance sanction or a stop notice; must not have relevant unspent convictions for fraud or tax offences; must not be formally insolvent; and must not be suspended or permanently banned from registering.
Firms with five officers or fewer declare all of them as relevant individuals. Firms with six or more identify those who make strategic or management decisions about the tax advice work and, if that produces fewer than five, nominate additional officers to reach five. Relevant individuals do not provide anti-money laundering evidence themselves, but they must not be disqualified from acting as a director in the UK or overseas.
Continued access to HMRC on behalf of clients now depends on the firm's own returns, supervision and officers. An adviser who misses their window will not be permitted to interact with HMRC for clients, and continuing to act after being told to stop can attract sanctions including financial penalties (HMRC guidance).
The fourth phase and financial services firms
The final window, 31 December 2026 to 31 March 2027, covers firms that already hold an agent services account and financial services organisations. HMRC's May announcement said the definition of that second group would follow in secondary legislation; by the July release HMRC said the definition had been published.
The guidance also carries an exemption. A business does not need to register where it interacts with HMRC for someone else because the law requires it to, even if it is paid; HMRC gives insolvency practitioners and some pension or investment firms as examples. So the position for a financial services firm depends on what it does, and an accountant should ask the financial planner they work with what theirs is.
What registration changes for the partnership with a financial planner
Nothing about what an accountant may say to a client. Describing idle cash on the balance sheet, no cover behind a personal guarantee, or a sale in motion is observation. Recommending a pension, product or investment is regulated advice for an authorised firm. Those situations are in six situations in the accounts that call for a financial planner.
What changes is that both professions will have been through the same HMRC registration, so who is registered to do what for a client has a short factual answer. The steps of the Altro partnership are in how the partnership works for one client.
Three things to do this week
- List every legal entity in your group and run HMRC's checker against each one. Companies, LLPs and sole trader registrations each count as an entity; the brand does not. If a newer entity has contacted HMRC in its own name without its own agent services account, its window closes on 18 August 2026.
- Find your anti-money laundering supervision certificate and confirm it is current and available digitally. HMRC wants a digital copy or a confirmation email.
- Do the relevant individuals exercise now. Count your officers, apply the five-or-fewer and six-or-more rules, and check that everyone on the list meets the conditions, including not being disqualified as a director anywhere.
What is not yet settled
The overseas evidence process is not live: HMRC's guidance tells overseas advisers their documents must be notarised and translated, but also says not to send evidence yet. The sanctions regime has guidance and no track record yet. How the fourth phase treats a firm that is both an existing account holder and a financial services organisation is the part to watch through the autumn, before that window opens on 31 December 2026.
Who takes regulated advice
The FCA's Financial Lives 2024 survey found that 8.6% of UK adults had taken regulated financial advice in the previous twelve months, and 13% of the self-employed. The lang cat's State of Advice Report 2025 put the average IFA client age at 59 and the average new client portfolio at £411,000. The wider picture is on the advice gap.
Common questions
Is 18 August 2026 the deadline for a practice that already has an agent services account?
No. HMRC's guidance says a firm that already has an agent services account does not need to register again at this stage. The 18 August 2026 window covers new tax advisers and advisers interacting with HMRC without an agent services account, Self Assessment or Corporation Tax account. Firms with an agent services account are in the final phase, 31 December 2026 to 31 March 2027, and HMRC will contact them through the account if it needs more information. Make sure someone reads the messages arriving there.
What counts as interacting with HMRC on a client's behalf?
HMRC's guidance says that if you interact with HMRC about someone else's tax affairs and are paid for it, you are treated as a tax adviser. Interaction includes phone, post or email, messages through the GOV.UK website or the HMRC app, making payments, and sending returns, claims or other documents. You need to register even if you do not describe your work as tax advice, even if you are a registered sole trader, even if tax is not your main business, and even if you act for one client.
Which window applies to a firm that also runs payroll for clients?
HMRC gives a separate window, 18 November 2026 to 18 February 2027, to advisers who solely provide third-party payroll services and do not interact with HMRC in any other way. A practice that files corporation tax returns and also runs payroll is not in that phase; it sits in the window that matches its account position. The legal entity registers, so a group that runs payroll through a separate company works out that company's window on its own facts.
Could our own firm fail HMRC's registration conditions?
Yes, if it does not meet them. HMRC requires evidence that the business is supervised for anti-money laundering, as a digital copy of the supervision certificate or a confirmation email. The business must not have relevant outstanding tax returns or unpaid tax unless covered by a payment plan, must not be subject to a decision refusing to interact, an anti-avoidance sanction or a stop notice, must not have relevant unspent convictions for fraud or tax offences, must not be formally insolvent, and must not be suspended or banned. Named relevant individuals must also not be disqualified as directors in the UK or overseas.
Does registration change what an accountant may say to a client about financial advice?
No. Registration concerns dealing with HMRC about tax. Describing surplus cash, missing protection or an approaching sale is observation. Recommending a pension, investment or product is regulated advice for an FCA-authorised firm. Both professions will be inside the same HMRC registration regime by 31 March 2027.