In terms of nominating which residence is a prime residence I keep coming across the following definition. "To be considered as a main residence for tax purposes, the property must be a dwelling house, or an interest in a dwelling house which is, or which at some point during the period of ownership been, the individual's only or main residence." As far a s I can see lots of people have a main home in the city and a country house which is used at weeek ends etc but when the main residence is sold lots of people will switch their nomination to establish the weekend property as their main residence. My question is by what set of rules does a week end cottage which has never been either a prime or only dwelling become able to be nominated a a prime residence. It clearly has never been a prime or only dwelling so I can only assume that it becomes a prime residence by dint of nomination. If that logic is true then my question is "How does the week end cottage become a residence"