Probably about a third of European airports don't offer fast track to BA customers for some or all aspects (e.g. Gold in GVA won't get it in Euro Traveller off the issued boarding pass). Mainly the smaller airports on the whole, where frankly it doesn't much matter.
Just to clarifiy: Priority Boarding is not a guesting privilege, however that is widely ignored. One certainly is allowed at all occasions that I've seen it happen, and often a great deal more than one guest.
Fast Track generally is also not always being given to a guest, however in certain locations it is, notably at LHR. For the documentation of T5, T3, T1 - where there is guest privileges for Fast Track to security - you can find it online here:
Originally Posted by BA.com
Fast Track Security is available for:
- all customers travelling in First, Club World and Club Europe
- British Airways Executive Club Gold and Silver members plus one guest
- oneworld Emerald and Sapphire members plus one guest
Guests need to go via the staffed gates since the automatic ones will now refuse entry.
T5
http://www.britishairways.com/en-gb/...on-heathrow-t5
T3
http://www.britishairways.com/en-gb/...on-heathrow-t3
T1
http://www.britishairways.com/en-gb/information/airport-information/london-heathrow-t1
For Emeralds/Golds and higher there is a concept of oneworld Fast Track, details are here:
http://www.oneworld.com/fast-track
Then we have Fast Track arrivals, which is for non EEA passengers. Details above, but at Heathrow it is guestable.