Originally Posted by
Jagboi
I've just used the airport address in the past. It's a US customs thing, not a BA IT thing, even when you are in transit the Americans still want an address that you are "visiting" in the USA.
AA has never demanded a full address from me when both legs have been operated by them — their system is able to compute the fact that I'm in transit from the fact that I'm in possession of an inbound and an outbound international coupon with a few hours between arrival and departure.