In any given tax year, a taxpayer can only designate a single property as their primary residence for that year, with the exception of a year in which they sell one property and buy another (called the “plus 1” rule). This restriction also applies to the family unit: the taxpayer, their spouse or common-law partner, and minor children. This means that a husband cannot designate one house as the principal residence while his wife designates another. This is true even if in reality they do not live together but instead each spend all their time in different homes. For tax purposes, they can only choose one of those residences to designate as primary and for which to capture the principal residence exemption. You are allowed to designate a different home as your family unit’s primary residence each tax year, however. So if a husband and wife live in different homes, they could alternate which home they designate as the principal residence year after year, thereby capturing half of the potential exemption for each property over time.