Originally Posted by
starless
I've been a dual citizen (US/UK) for some time, and I also became French last year
With United I've always listed my US passport as the one I'm traveling on, then when arriving in UK or EU I show my other passport.
My main reason for saying I'm using my US passport as that's the one that's linked to my Global Entry membership and so provides TSA-Pre.
If I told United I was using my UK (or French) passport, would I still be able to have TSA-Pre outbound?
For departures, TSA Pre√ keys of the Known Traveler ID and not passport. For inbound to US, you’ll want to use the passport that has GE.