Tax adviser registration: what conveyancers need to know

What changed

The Finance Act 2026 brought in mandatory registration for tax advisers who interact with HMRC on behalf of clients. The requirement came into force on 18 May 2026, and HMRC gave advisers three months to apply.

For conveyancers, the trigger is the work rather than the title. HMRC's guidance says registration depends on the activities a business carries out. A conveyancer is likely to need to register if the firm:

• submits SDLT returns to HMRC for clients
• deals with HMRC about a client's SDLT
• makes SDLT payments on a client's behalf

Giving general information about rates, reliefs or deadlines doesn't on its own bring a firm into scope. Where filing is outsourced, HMRC expects both businesses to register.

What it means for your files

Registration puts SDLT work in plain sight. The Law Society's view is that firms are "likely to retain ultimate responsibility for submitting SDLT returns", even where part of the work is passed to someone else. A line in the engagement letter saying "we do not give tax advice" is harder to rely on when the firm is registered as a tax adviser and files the return.

HMRC is also looking harder. Stamp duty investigations rose 88% to 3,035 in the year to 5 April 2025, according to HMRC figures obtained under Freedom of Information by Lubbock Fine. Under the new rules for tax advisers, HMRC can charge up to £3,000 for each careless or deliberate inaccuracy in documents a firm gives it, and up to £1 million for a first penalty for sanctionable conduct, which requires intent.

The question an HMRC officer will ask is simple: how did you get this figure? On most files today the answer is a fee-earner's note of a phone call and one number from a calculator.

What to do now

• Check where you stand. Confirm whether the firm has registered, and who in the firm deals with HMRC on SDLT.
• Review engagement letters. Make sure they describe what the firm actually does on stamp duty, not what you'd like to exclude.
• Fix how the facts are gathered. The client is the only person who knows whether they own a share of a flat abroad or are keeping their old home. Get their answers in writing, not second-hand.
• Flag complex cases early. Separations, inherited shares, mixed-use claims and company purchases need a tax adviser, and the client needs to know that before exchange.
• Keep the record. Every question asked, every answer given, the result, and the client's decision on advice, with a date and time.

How Stamp helps

Stamp moves the stamp duty questions from your fee-earner to your client. The client answers on their own phone, and complex cases are flagged with a low and a high figure and the reason. The same timestamped PDF goes to the client and to your file. Stamp has no in-house tax advisers: where advice is needed, the client chooses an independent firm from the panel, or uses their own adviser.

It reduces your risk and leaves you a defensible file. It doesn't change who is responsible for the return.

Sources

• Legal Futures: HMRC explains when conveyancers should register as tax advisers (June 2026)
• Law Society Gazette: guidance for conveyancers on HMRC registration
• GOV.UK tax adviser registration guidance, reported by Today's Conveyancer
• GOV.UK: how HMRC deals with tax adviser sanctionable conduct
• MoneyWeek: HMRC stamp duty investigations up 88% (January 2026)

This article is general information, not tax advice. Rules change: check the date above. Last updated October 2026.