How stamp duty works

Stamp Duty Land Tax is charged in slices, the same way income tax is. Each portion of the price is taxed at that portion’s own rate, so crossing into a higher band only ever raises the tax on the pounds above the threshold, not on the whole house. The one place that logic breaks is first-time buyer relief, which is covered below.

First-time buyer relief is not tapered. At £500,000 you pay £10,000, and at one pound more the relief disappears for the entire purchase and the standard rates apply to all of it, which comes to £15,000. That single pound of price costs £5,000 in tax.

If you are offering near the cap, this is worth having in your head during the negotiation rather than after it. Relief also requires every buyer to be a first-time buyer: buying with a partner who has owned before, anywhere in the world, means the standard rates apply to the whole purchase.

Additional properties carry a surcharge on every band, currently five percentage points, so this is only right for the home you are going to live in. Non-UK residents pay a further surcharge on top, and Scotland and Wales have their own taxes with their own bands (Land and Buildings Transaction Tax and Land Transaction Tax), which this tool does not attempt. The First Move itself only covers England, so the calculator matches the app.

The bands and rates here are the statutory ones published by HMRC, in force since 1 April 2025, last checked against gov.uk on 19 July 2026. Rates change at Budgets, so for anything you are about to sign, check gov.uk’s official rates page. This is arithmetic on published rates, not tax or financial advice.