Travelling through the Common Travel Area
he UK, the Republic of Ireland, the Channel Islands and the Isle of Man are known as the Common Travel Area.
If you are a visa national, or if you are recognized as 'stateless', you may need a visa to transit the UK on your way to or from a Common Travel Area destination.
Travelling to a Common Travel Area destination
If you are passing through the UK on your way to a destination in the Common Travel Area, you cannot transit air side and will need to enter the UK during your journey