State tax on the registration of a sale, typically 5–7% of the higher of the agreement value and the government's guidance value.
How it works and what to check
Stamp duty is a state tax, so the rate differs by state and sometimes by the buyer (several states charge women buyers less), the area (urban or rural) and the value. It is charged on the higher of the price in the deed and the state's guidance or circle value for the property.
It is paid before registration, usually by e-stamp paper or an online challan, and the registration fee is charged separately. Underpaying can lead to the deed being impounded and a penalty.