Introduction to Stamp Duty Land Tax: Rates of tax (SDLT) - FA03/S55
The amount of SDLT chargeable is calculated using a marginal rate system, with each rate of tax applying the portion of the chargeable consideration that falls within each tax band. The amount calculated is round down to the nearest pound.
Chargeable consideration is defined at SDLTM03700.
The rates applicable are determined by whether the land in question is wholly or partly non-residential (see SDLTM00365) and by the amount of the chargeable consideration.
If a transaction is linked to another chargeable transaction the rates applicable are determined by reference to the sum of all linked chargeable transactions, unless multiple dwellings relief can be claimed. See SDLTM29900.
Transactions, which are linked can be reported on the same land transaction return and the purchasers will be treated as joint or common purchasers. See SDLTM30100.
For SDLT rates and thresholds see the Stamp Duty Land Tax Overview page on GOV.UK.