Question to the Home Office:
To ask the Secretary of State for the Home Department, what the maximum amount of time is that a person can be detained in an immigration removal centre.
Although there is no fixed time limit on immigration detention in the UK, case law is clear that, to be lawful, detention must last no longer than is reasonably necessary to achieve the purpose for which it was authorised, must not be unduly prolonged and, in relation to removal, there must be a realistic prospect of removal within a reasonable period of time. Published Home Office policy is clear that detention must only be used for the shortest period necessary.
https://www.gov.uk/government/publications/offender-management