STOP PRESS: This Practice Note is being updated for Statement in Changes HC 584, see: LNB News 03/09/2026 37 (Fee waiver application date does not count for 3C leave if no human rights application submitted, and Biometrics have to be completed even if application varied). Changes in force for applications from 8 October 2026. In this Practice Note, the terms ‘leave to enter/remain’ and ‘permission to enter/stay’ are used interchangeably. The word ‘permission’ replaces ‘leave’ in the Immigration Rules for simplified routes, but the former term is still used in other categories of stay and the relevant legislation. A person with permission to enter or remain in the UK, who wishes and is permitted to apply to stay beyond the date their current leave expires, or who wishes to change immigration route is generally required to make an application when in the UK to the Home Office to vary their permission. A person’s permission may be varied: • by restricting, enlarging or removing the limit on its duration, or • by adding, varying or revoking