‘Even if you don’t think you’re a tax adviser, your firm might be affected’: HMRC tax adviser registration

The Finance Bill 2026 is in its final stages of passing through parliament, on its course to royal assent by April this year.

HM Revenue and Customs (HMRC) has made it clear that this will include mandatory tax adviser registration – directly affecting many of our members, who will need to act within the coming weeks to be prepared.

The department has now released the first iteration of official guidance for businesses and individuals that interact with HMRC on behalf of clients – asking you to check if you meet the conditions to register and if so, by when.

The guidance does not add much to what has already been said in draft legislation, except that registration is set to start from 18 May 2026 and will be via an online agent services account.

HMRC’s description of ‘tax adviser’ is broad in scope:

“If you interact with HMRC about someone else’s tax affairs and get paid for it, we consider you to be a tax adviser. This means you’ll need to register for an agent services account.”

Understanding the ‘tax adviser’ label for solicitors

Even if you don’t think you’re a tax adviser, your firm could be affected – from sole practitioners through to large firms.

Registration will be at firm level, and the number of ‘relevant individuals’ required on the register is determined by the firm’s size.

It might be that you are a conveyancer submitting stamp duty land tax (SDLT), or you communicate with HMRC systems when working on family law matters.

You might be in a private client team that deals with inheritance tax forms.

These practice areas have generated the most discussion, but once you take in the breadth of incidental tax advice given across the profession, the reach goes far beyond that.

The guidance sets out an initial outline of the conditions that businesses of varying sizes should expect to meet, as well as those identified as ‘relevant individuals’.

A second round of guidance is expected soon, including more information on how to register.

There are still many questions to answer, and this is something we’re working on with HMRC to minimise disruption to members.

Our view on tax adviser registration

As things stand, the conditions for registration are too broad and imprecise in scope to be meaningfully applied to those in our profession.

We’ve been in an ongoing dialogue with HMRC since its consultation on modernising and mandating tax adviser registration with HMRC in September 2025.

Our response explained why any changes introduced should be proportionate and account for the existing framework of the Solicitors Regulation Authority (SRA).

Since then, we have pushed for firms regulated by the SRA to be passported onto the register, or for a carveout for firms that have incidental tax functions without providing specialist advice.

We’ve also highlighted the pitfalls of double regulation and of granting HMRC wide discretionary powers without adequate safeguards.

Our concerns extend to how the private tax affairs of those identified as ‘relevant individuals’ will be monitored and the impact this may have on a firm’s presence on the register – as well as the potential to draw out and destabilise well-established processes such as buying and selling properties.

How tax registration will affect different sized firms

Mark Sellers, real estate partner at Penningtons Manches Cooper and co-chair of our Conveyancing and Land Law Committee (CLLC), is at a firm with over 100 conveyancers.

Even with a ‘know-how’ team to help keep on top of regulatory changes and other fast-moving developments in property, he says it still amounts to a huge administrative burden.

“We have three people in real estate who I can raise this with, but they are very busy on a variety of things from commonhold to upwards only rent reviews, day-to-day property work, building safety and all the rest.

“We could be dealing with hundreds of transactions every month.”

There are challenges for smaller conveyancing firms too, says sole practitioner Sarah Dwight and fellow CLLC co-chair.

“A smaller firm will not have the same level of admin support. Many partners in small firms will say I'm just going to have to do it myself. It’s going to create some inequality.

“And it could even be the case that a smaller conveyancing firm like mine or even a two- or three-partner firm may decide, ‘You know what? We're not going to do conveyancing’.”

An awareness problem amongst conveyancers

“When you hear ‘tax adviser’, most conveyancers will think, ‘I'm not a tax adviser’, so they won't pick it up,” says Mark.

“If it said, ‘Do you do SDLT returns?’, they’d say, ‘Oh gosh, what now?’”

The definition of ‘tax adviser’ is so broad that, at a time when conveyancers are already grappling with numerous challenges to their practice, the available HMRC guidance has not yet cut through to those most likely affected.

HMRC’s lack of communication with solicitors is concerning, given it is allowing only a three-month transition period from the expected start on 18 May.

“A lot of conveyancers aren't even aware that this is going to happen,” says Sarah.

What’s next

Like many of you, we still have questions that need answers.

If the government will not adopt our common sense recommendations, it must ensure the little time left before this comes into force is used effectively.

HMRC must commit to raising awareness of these new obligations among solicitors to avoid additional burdens being placed on our members and HMRC alike.

Every firm – no matter the size – needs clear information and support to comply.

Explore HMRC’s latest guidance

On 17 February 2026, HMRC published two separate pieces of guidance:

• check if you meet HMRC’s conditions to register as a tax adviser
• check if and when you need to register as a tax adviser with HMRC

More guidance is expected to be published before 18 May 2026.

Our message to government

Read our policy position on mandatory tax adviser registration in our response to the government’s consultation on the tax advisory market and draft Finance Bill 2025-26 in September 2025.