SDLT 3% Surcharge Refund UK 2026 — Claiming Back the Additional Dwellings Charge

Who qualifies for the SDLT surcharge refund?

The refund applies in a specific, narrow set of circumstances:

• You bought a new main residence: The purchase to which the 3% surcharge applied must have been your intended main residence — not a buy-to-let or investment property. You must have intended to live in the property as your main home
• You paid the 3% surcharge at completion: The surcharge was applied because you still owned another residential property at the date of the new purchase
• You have since sold the previous main residence: You must have sold (completed the sale of) your previous main home within 3 years of completing the new purchase
• The previous property was your main residence: The property sold must have been your main residence at some point. HMRC may query a sale that qualifies if the property was let for the entire period and never occupied as a main home
• You claim within the deadline: The refund claim must be made within 12 months of the sale of the previous main residence OR within 12 months of the filing date for the SDLT return — whichever is later. Miss this window and the refund is lost permanently

How to calculate the refund

The refund amount equals the additional 3% that was charged on the original purchase:

• Refund = 3% of the total purchase price: If you paid £450,000 for your new home, the 3% surcharge component was £13,500. That is the refund amount
• Applies to the whole purchase price: The 3% surcharge is applied to the entire consideration — not just the amount above the threshold. A £450,000 purchase attracts a 3% surcharge of £13,500 regardless of how much SDLT was payable at the standard rates
• Mixed-use and other complications: Where the original SDLT return was complex (e.g., a mixed-use property, or MDR was claimed before June 2024), the refund calculation must be reconciled against the original SDLT paid. HMRC's online refund form guides the calculation
• No interest paid on refund: HMRC does not pay interest on the refunded SDLT, even where a long delay occurs between payment and refund

Step-by-step: how to claim the SDLT refund

The claim is made online through HMRC's portal:

• Step 1 — Gather documents: Collect the original SDLT return (form SDLT5 or completion statement showing SDLT paid), the completion statement or transfer deed for the new purchase, and the completion statement or transfer deed for the sale of the old main residence
• Step 2 — Use HMRC's online form: The refund is claimed via HMRC's online 'Stamp Duty Land Tax — online returns and payment' service. Navigate to 'Claim a refund of SDLT additional dwellings supplement'. You will need the UTRN (Unique Transaction Reference Number) from the original SDLT return
• Step 3 — Complete the claim: Enter details of the original purchase (date, price, SDLT paid, UTRN), the new main residence, and the sale of the previous property (completion date, sale price, buyer's details). HMRC will verify the details against their records
• Step 4 — Processing time: HMRC aims to process refund claims within 15 working days. In practice, complex or queried claims can take 3-6 months. If delayed, contact the HMRC Stamp Taxes helpline
• Step 5 — Receive the refund: HMRC issues the refund by cheque or bank transfer to the solicitor who submitted the original SDLT return, unless otherwise specified. Confirm the payment destination when submitting the claim

Common mistakes and rejected claims

Several factors lead to refund claims being queried or rejected:

• Missing the 3-year deadline: The most common error. The 3-year window runs from the completion date of the new purchase. If the old property is not sold within 3 years, the right to claim the refund is permanently lost, regardless of the reason for the delay
• Missing the 12-month claim deadline: Even where the old property is sold within 3 years, the refund claim must be submitted within 12 months of that sale (or 12 months from the original SDLT return filing date if later). Many buyers miss this because they do not know the claim window exists
• The property was not a main residence: HMRC will reject claims where the 'previous main residence' sold was primarily an investment property and the buyer never occupied it. Some evidence of occupation (utility bills, electoral register, Council Tax) may be requested
• The new purchase was not a main residence: Where HMRC believes the new purchase was itself a buy-to-let — for example, where the buyer continues to rent elsewhere and does not move into the property — the refund will be refused
• Property sold to a connected person: Where the previous main residence is sold to a connected person (family member, company under the buyer's control), HMRC may treat this as a non-qualifying disposal and refuse the refund

Landlord-specific situations — when the surcharge applies and doesn't

For landlords who own buy-to-let property, the surcharge rules are layered:

• Buying a buy-to-let when you already own one: The 3% surcharge always applies. No refund is available — it is not a main residence purchase
• Buying a new main home while retaining a buy-to-let: If a landlord buys a new main home and already owns buy-to-let property, the 3% surcharge applies to the main home purchase. The refund route is NOT available — the landlord owns other residential property that is not being sold in conjunction with the purchase
• Buying a new main home while also owning the old main home (temporarily): If a landlord owns a buy-to-let AND their main home, and then buys a new main home (with the old main home not yet sold), the 3% surcharge applies. Provided the old main home is sold within 3 years, the refund IS available — even though the buy-to-let continues to be owned. The refund is not affected by other investment properties
• Purchasing with a bridging loan: Some landlords use a bridging loan to buy the new home before the old one sells. In these cases, the 3% surcharge is paid at completion and reclaimed when the old home sells within 3 years. This is a common and legitimate strategy
• The key test is whether there is a previous main residence being replaced — not whether other investment property exists

Frequently asked questions