Stamp Duty Surcharge Refund Calculator (England & NI)

If you bought a new main home before selling the old one, you paid the additional-property surcharge on the whole price — and you can claim every penny back if the old home is sold within 36 months. This calculator works out the surcharge you paid (the rate depends on when you completed: 3% from April 2016, 5% from 31 October 2024), the last date the previous home must be sold by, and the deadline for the repayment claim.

Who qualifies for the repayment

• You bought a new main residence and, at that moment, still owned your previous main residence, so the higher rates applied.
• You then sold (or otherwise disposed of) the previous main residence within 36 months of buying the new one.
• The property being sold was your only or main residence at some point in the three years before the new purchase — a long-let buy-to-let that you never lived in does not count.

How much comes back

The refund is the difference between the higher-rates SDLT you paid and the standard SDLT that would have applied — in practice, the surcharge percentage multiplied by the price (properties under £40,000 were never surcharged). On a £400,000 purchase completed after 31 October 2024 that is £20,000; before that date it was £12,000. HMRC pays interest on the refund from the date it received the original SDLT.

The claim deadline that catches people

You must claim within 12 months of the sale of the previous home, or within 12 months of the filing date of the SDLT return for the new home, whichever is later. The SDLT return is due 14 days after completion, so for most people the practical deadline is 12 months from selling the old house. Miss it and HMRC will not repay. (Source: gov.uk “Apply for a refund of Stamp Duty Land Tax” and HMRC’s higher-rates policy paper, which puts the 3-year window and the 12-month application rule in Schedule 4ZA FA 2003 — re-read 4 September 2026.)

How to claim

Online through HMRC’s “Apply for a repayment of the higher rates of Stamp Duty Land Tax” service, or by post. You need the SDLT unique transaction reference (UTRN) for the new home, the addresses and dates of both properties, and the amount paid. Repayments usually arrive within about 15 working days when the claim is complete.

Scotland and Wales

Scotland’s Additional Dwelling Supplement (ADS, 8%) and Wales’s LTT higher rates have their own repayment rules and windows — this calculator is for SDLT (England and Northern Ireland). See Scotland and Wales.

Landlords: when this does not help

The repayment is a replacement-of-main-residence rule. Selling a rental to buy another rental never qualifies; nor does keeping the old home and letting it out. If you are weighing that choice, the CGT calculator and the rental income tax calculator show the other side of the ledger.

Rates, windows and the claim deadline re-checked against gov.uk on 4 September 2026 (research/2026-09-04). General information, not advice.