About this site

What this site does

Stamp Duty Calculator is a free, no-signup tool for working out UK Stamp Duty Land Tax (SDLT) on residential property purchases in England and Northern Ireland. It supports standard purchases, first-time buyers, additional properties (second homes and buy-to-let), and the 2% non-UK resident surcharge.

Alongside the calculator we publish a longer SDLT guide and a frequently asked questions page covering the rules, common edge cases, and the kinds of situations buyers and their solicitors run into.

How we keep the rates accurate

The calculator uses the published HMRC residential SDLT rates in force from 1 April 2025 onwards. We review the rates after every UK Budget and Spring Statement, and any time HMRC publishes a change. The current rate tables are mirrored on the calculator page and explained in detail in the guide.

Calculation logic is unit-tested against a battery of worked examples spanning every band, every buyer type, and the surcharge threshold edge cases. We track every rate change in a public changelog (see the guide for the recent history of SDLT changes).

What this site is not

We are not a regulated financial adviser, accountant, solicitor or conveyancer. The calculator gives you a guidance figure based on the headline SDLT rules; it cannot capture the full set of rules for things like mixed-use properties, shared ownership staircasing, linked transactions, transfers between connected parties, or purchases by companies and other non-natural persons. Always confirm the exact SDLT figure with your solicitor or HMRC before completing.

Contact

For corrections, feedback or partnership enquiries, email contact@dutycalculatorstamp.co.uk. We try to respond within a few working days.