827. The principal residence relief.

No part of a gain attributable to the disposal of eligible property1 is a chargeable gain if the dwelling house has been the individual's only or main residence either:

  1.  

    (1)     throughout the period of ownership2; or

  2.  

    (2)     throughout the period of ownership except for all or any part of the last 18 months, reduced to 9 months for disposals after 6 April 20203, of that period4.

If neither of those two conditions is satisfied, a fraction of the gain is not a chargeable gain5, that fraction being:

  1.  

    (a)     the length of the part or parts of the period of ownership