What qualifies as a genuine main residence?
Private Residence Relief (also known as Principal Private Residence Relief) depends on the property genuinely having been the individual's only or main home for qualifying periods of ownership, and on other statutory conditions. A buy-to-let purchased purely as an investment does not become a qualifying residence simply because an owner nominates it.
Married couples and civil partners living together generally have only one main residence between them for a given period. Where more than one residence genuinely exists, nominations and their deadlines can be relevant, but facts still matter.
A former home that was subsequently rented out
Relief is generally available for the actual qualifying period of residence and, where the property was a qualifying residence at some point, the final nine months of ownership under the ordinary rules. The exempt part of the gain is normally calculated by reference to qualifying periods of ownership, with relevant adjustments.
For example, somebody who lived in the property for several years and then let it for a prolonged period may have a partly relieved and partly chargeable gain. Keep evidence of the dates of genuine occupation, departure, lettings, sale and any permitted absences.
Does an overseas work posting preserve the relief?
Some periods of absence can count as deemed occupation, including qualifying overseas employment absences, subject to statutory conditions. These are not automatic exemptions for every expatriate. In many cases qualifying occupation before and after the absence, or a work-related exception, must be considered.
For tax years from 2015/16, special residence/occupation tests can affect relief for a home in a country where the owner is not tax resident. The 90-day occupation test may be important for overseas owners, with detailed household and nomination rules. Do not assume a UK former home qualifies for every year of non-residence.
Letting Relief is much narrower than many landlords think
The current relief for letting part of a home is generally targeted at situations where the owner shared occupancy with a tenant. Letting the whole property to tenants after moving away does not ordinarily produce the old, broad letting relief that some historical articles describe.
Separately, qualifying periods of absence and the final nine months can produce some PPR in appropriate cases. These concepts should not be conflated.
Timing, evidence and tax returns
Before deciding when to sell, compare the acquisition and ownership dates, qualifying periods, rental history, property improvements, other property ownership and expected completion. For a non-UK-resident vendor, the 60-day UK property disposal return may be needed even if relief means there is no tax to pay.
If there is an existing tenant, practical sale arrangements and the legal position on vacant possession are separate questions from the CGT calculation.