Joan and Peter buy a house together for €250,000 in June 2017.
An instrument is executed to transfer the house into their joint names.
They pay Stamp Duty on €250,000 at the rate applicable to transfers of residential property.
Unfortunately, their relationship breaks down.
They agree that the house should be transferred entirely to Joan.
Joan is not paying any consideration.
Peter executes an instrument on 15 October 2018 to transfer his share of the house to Joan.
The market value of the (whole) house at that time is €280,000.
As Joan already owns half of the house, she is liable to pay Stamp Duty on €140,000.
Joan and Peter may have taken out a mortgage when they bought the house.
Specific rules apply if Joan assumes responsibility for paying the mortgage.
For more information, see Stamp Duty and Consideration.