Assistance dogs may travel if they are registered with The Pet Travel Scheme (PETS) and if allowed by the airline and the destination.
Registered assistance dogs travelling to destinations in the UK do not need to be registered with the PETS.
If you are travelling with a non-EU carrier different rules apply. Whilst many airlines will accept assistance dogs it is worth checking with them directly.
If you are travelling through Belfast International Airport, dog toileting facilities will be made available on request.