Marriage/ Civil partnerships and your Main home
If both individuals, due to get married or enter into a civil partnership own separate property which they continue to occupy for a significant length of time, they are required to nominate one of them as their main home within two years of their marriage or civil partnership. Once they are married, they are only allowed one main property for tax purposes, it is therefore tax efficient to nominate the property that is most likely to utilise the Capital Gains Tax Property Exemption. If you fail to nominate a main residence, HMRC will simply designate the property which you are resident at most often as your main residence.