Stamp duty letters of authority: when HMRC needs one

Letters of authority and SDLT

HMRC says it needs signed permission before dealing with a different agent or sending an SDLT refund to an agent.

• Each joint buyer must sign.
• A refund needs clear consent for payment to the agent.
• This is HMRC guidance, not legislation.

Scroll down for the full analysis.

Stamp duty letters of authority: when HMRC needs one

HMRC may require a signed letter before discussing your stamp duty land tax case with a new agent. It also requires one before paying an SDLT refund directly to that agent. Without it, HMRC may delay the discussion or payment.

What this rule is about

Your SDLT return records any agent you used. This could be your conveyancer or tax adviser. At a later stage, you may want someone else to deal with HMRC.

HMRC’s manual explains how it manages that change. The letter tells HMRC that your new representative may act for you.

What the official source says

HMRC says it will not discuss an SDLT matter with an agent other than the agent named on the return until it receives a letter of authority. The letter must permit the different agent to act for you.

• The buyer must sign the letter.
• Every buyer must sign where the purchase was joint.
• You must send the letter before HMRC discusses the matter with a different agent.
• HMRC provides a letter template in its SDLT manual.

What this means in practice

Your new adviser cannot discuss the case. Send the signed authority first. This is especially important when someone takes over an older SDLT issue.

You must take a further step if an agent asks HMRC to send an SDLT refund to the agent instead of to you.

• You need this requirement even if the agent was named on the SDLT return.
• The letter must confirm your agreement that the refund be paid directly to the agent.
• Each joint buyer must sign that confirmation.
• HMRC says it must receive the letter before processing the repayment.

How to analyse it

Begin by asking who HMRC has on record. Then check who now wants to speak for you or receive the repayment.

• Find the SDLT return and identify any agent named there.
• Check whether a different agent wants to contact HMRC.
• Check whether the property was bought by one person or jointly.
• If you request a refund, check who should receive the money.
• Use HMRC’s template, or make sure the letter covers the same points.

Example

Amir and Priya bought a home jointly, and their conveyancer filed the SDLT return. A different tax agent later finds that they may be due a refund. The new agent asks HMRC to pay the refund to its firm. Amir and Priya must both sign. HMRC’s manual requires a letter allowing that payment before HMRC processes it.

Why this can be difficult in practice

One buyer cannot sign for everybody. This assumption is common. For a joint purchase, HMRC’s stated position is that each buyer must sign.

Another common mistake is focusing only on the refund claim. Even when the claim is ready, if the refund is to go to the agent rather than to you, and if HMRC has not received separate permission, HMRC says it needs that permission before paying the money. The claim alone is not enough.

• An agent’s name on the original return does not remove the repayment authority requirement.
• Case-discussion authority differs from consent to receive a refund.
• HMRC’s manual is guidance about its process, not legislation.

Key takeaways

• Give HMRC signed authority before a new agent discusses your SDLT case.
• For a joint purchase, every buyer should sign.
• Give clear written consent if a refund should go to an agent.

Technical analysis

For advisers, and for anyone who wants to check the law behind this page. You do not need this section to understand the guidance above.

Official guidance

The pages below are HMRC’s guidance. Guidance is not law. It sets out how HMRC reads the legislation, and it is not binding on you, on a tribunal or on a court. Where guidance and the legislation differ, the legislation wins. HMRC can also change or withdraw guidance, and it may not cover your facts.

• SDLTM61500
• SDLTM61510

Where this is not settled

• The source does not say what HMRC will accept if a buyer cannot sign.
• The source does not explain whether a separate letter is needed where a refund will be paid to the buyer instead.
• HMRC can change its manual or its preferred letter format.

Evidence you would need

This kind of case is decided on the facts of the individual property. These are the records that usually settle it, and the ones an adviser would ask you for.

• the SDLT return showing the agent originally named
• a signed letter from each buyer where the property was bought jointly
• clear confirmation that any refund may be paid to the agent
• the SDLT transaction and refund details the authority covers

Explore this with an AI

An AI will give you plenty of information. It will not take responsibility for any of it. When a conveyancing solicitor asks for professional tax advice, responsibility is what they are really asking for: a named adviser who has looked at your facts and carries indemnity insurance for the view they reach.

Email me your circumstances and I will give you my honest opinion, free. About half the time that is the end of it. If your solicitor wants it in writing, a formal letter of advice starts at £350, no VAT.

If it helped and you never need the letter, a Google review or a charity donation is welcome. Never expected.

Email me about your situation[email protected]

Nick Garner

Readers often want to test their own situation. Copy the prompt below into ChatGPT, Claude or Gemini. It hands the model the actual legislation for this page rather than letting it answer from memory, and tells it to be explicit about what is uncertain. What comes back is information, not advice – check it against the links above.

I am researching UK Stamp Duty Land Tax (SDLT), which applies in England
and Northern Ireland.

MY QUESTION
Stamp duty letters of authority: when HMRC needs one

[Replace this with your own situation: what you are buying, the price,
the dates, who the buyer is, and what you plan to do with the property.]

HMRC's guidance page on this topic (guidance, not law):
https://www.gov.uk/hmrc-internal-manuals/stamp-duty-land-tax-manual/sdltm61500

HOW I WANT YOU TO ANSWER
1. Work from the legislation above. Read it before answering. HMRC
   guidance is HMRC's view of the law, not the law, and does not bind a
   tribunal or a court.
2. Tell me what the rule actually requires, in plain English.
3. Tell me which facts decide the answer, and which facts would change it.
4. Tell me what evidence I would need to support the position.
5. Be explicit about anything unsettled or fact-sensitive. Do not guess.
6. Your training data has a cutoff and SDLT rates and reliefs change at
   fiscal events. Say so if you are not sure the law is current.

POINTS ALREADY KNOWN TO BE UNCERTAIN ON THIS TOPIC
- The source does not say what HMRC will accept if a buyer cannot sign.
- The source does not explain whether a separate letter is needed where a refund will be paid to the buyer instead.
- HMRC can change its manual or its preferred letter format.

Do not give me a conclusion you cannot support from the provisions above.

Legislation links show Finance Act 2003 as it stood on 2025-11-17. The law may have changed since, and the rules that apply are those in force on the date of your transaction. The official guidance this page is based on is here.

This page was last updated on 1 September 2026

Useful article? You may find it helpful to read the original guidance here: Stamp duty letters of authority: when HMRC needs one

View all HMRC SDLT Guidance Pages Here