Stamp duty is typically taxed when you are buying immovable property. Some states in India levy their own stamp duties, while the others. just follow the central Stamp Act of 1899. In Tamil Nadu, the standard stamp duty rate is 7% of the total market value of the property. But recently, in 2013, an extra stamp duty of 1% was introduced for registering the construction agreement. So you can now think of it as 8% for practical purposes. You can pay the stamp duty by buying stamp paper of the same amount and printing the sale deed on them or by simply getting the sale deed franked.