How to Claim a Stamp Duty Refund on Your Additional Dwelling Surcharge

When Are You Entitled to a Refund?

When you purchase a new home before selling your existing main residence, HMRC requires you to pay the additional dwelling surcharge — currently 5% — on top of standard SDLT rates at completion. This is because at the point of completion, you own two residential properties.

However, the law recognises that this is often a timing issue rather than a genuine purchase of a second home. If you sell your previous main home within **36 months** of completing on the new purchase, you are entitled to claim back the full 5% surcharge. This refund is a statutory right, not a discretionary concession.

It can represent a very significant sum. On a £500,000 purchase, the 5% surcharge amounts to £25,000 — money that is rightfully yours to reclaim once the old home is sold.

Step-by-Step: How to Claim

**Step 1: Confirm you qualify**

• You paid the additional dwelling surcharge when purchasing your new home
• You have since sold (or otherwise disposed of) your previous main home
• The disposal occurred within 36 months of the date you completed on the new purchase
• The property you disposed of was your previous main residence (not another investment property or secondary home)

**Step 2: Gather your documents**

You will need:

• The Unique Transaction Reference (UTR) for your original SDLT return — this is on the SDLT5 certificate your solicitor provided at the time of purchase
• The completion statement from your new property purchase
• The completion statement from the sale of your previous home (your solicitor or the estate agent's records will have this)
• Your bank account details for the refund payment

**Step 3: Submit the claim to HMRC**

The claim is made using HMRC's online portal at www.gov.uk/guidance/stamp-duty-land-tax-apply-for-a-repayment-of-the-higher-rates-for-additional-dwellings. You will need a Government Gateway account.

Alternatively, you can claim by post. Download the SDLT claim form from the GOV.UK website and send it to: HMRC SDLT, BX9 1HD. Postal claims take significantly longer to process.

**Step 4: Wait for processing**

Online claims are typically processed within 15 working days. Postal claims can take 8–12 weeks or more.

**Step 5: Receive your refund**

HMRC pays the refund directly to the bank account provided in the claim. There is no interest paid on refunds, regardless of how long processing takes.

What If You Cannot Find Your SDLT Return Reference?

The SDLT5 certificate issued at the time of purchase contains the Unique Transaction Reference needed to make the claim. If your solicitor no longer trades or you cannot locate the certificate, contact HMRC's SDLT helpline on 0300 322 7835. They can search for the transaction using the property address and completion date.

Claims Made by a Solicitor

You can authorise your solicitor to make the claim on your behalf. Your original conveyancer is often best placed to do this as they hold the relevant transaction documents. Many solicitors will charge an additional fee for this service — check before engaging them.

Rejected Claims

Claims are sometimes rejected if HMRC is not satisfied that the previous property was the buyer's main home, or if the 36-month window has expired. If your claim is rejected, you have 30 days to request a review. See our guide on what to do if your stamp duty refund is rejected for the full appeals process.

Use our Stamp Duty Refund Calculator at Property Passport UK to calculate exactly how much surcharge you paid and are entitled to claim back, based on your purchase price — so you know the exact amount before you apply.