Originally Posted by
Saladman
If you remain airside then a transit visa is not required at all.
Just for information and for the information of anyone else reading the thread, transit visas are only required if you need to enter landside; i.e. actually 'entering' the country.
With some passports, you actually
do need a transit visa for the UK (
a "Direct Airside Transit visa") even if you stay airside and never cross the UK border:
You might need a Direct Airside Transit visa (DATV) if you:
- will be changing flights in the UK on your way to another country
- will not go through UK border control [my emphasis]
To note, this doesn't apply to Ukrainian passport holders, but conversely Pakistani passport holders (for example)
do need a DATV just for transiting through the UK even without crossing the UK border, en route to a non-UK/Ireland/CTA destination.