Marriage Value (MV) is a term used in the context of UK housing to refer to the increase in value of a property when two individuals who are not married or in a civil partnership buy it together. It is applicable to individuals who are buying a property for the first time and to those who already own a property. Marriage Value is determined by calculating the difference between the combined value of the two individuals’ existing properties (if applicable) and the value of the new property. The purpose of MV is to ensure that the taxation of jointly owned property is fair and equitable, and that those who are not married or in a civil partnership receive an appropriate value for their investment. Marriage Value is calculated on the whole value of the property and not just the proportion of ownership.