 In theory, possession of a family permit is not mandatory and permission to enter the UK can still be sought at the frontier, but non-EEA nationals who neither possess a visa nor a family permit will find it difficult to arrive at the UK border as many carriers will refuse boarding to passengers who do not hold a family permit, as they may be fined by the British authorities for carrying a visa-required national without a visa or family permit.In addition, family members are sometimes refused entry to the UK for failure to have a family permit.A family permit can be issued for a short visit or to enable the holder to take up residence in the UK.