Security Taxes--International
Not 100% sure about taxes on jumpseaters, but it is definitely true for pass-riders. I tried to do this a year ago on vacation from Europe, coming home. Needed to call UAL Crew Desk in Chicago.....I think it was 24 hours prior. Problem was, I could only list myself as a jumpseater on one flight...and there were 5 to choose from; all tight.
Given the roulette-nature of picking the right flight, and I didn't have a phone that could call internationally, I just paid the taxes as a pass-rider. Fairly high; I think it was $100 a person.
Jumpseating from the US to overseas is not that tough (although getting into the international terminal without a ticket is!). But the return sure is.