Originally Posted by
Athena53
It depends on the airport. My home airport is MCI so, sadly, very few international nonstops (except those to Mexico and now Icelandair to KEF). I see no reason to be there 3 hours early for a flight that's going to connect in ORD to an international flight. The only extra work they need to do at MCI is verify my passport.
I do try to allow 2-3 hours if it's an airport where I have to go through "security" AND passport control.
The above is my process. My home airport is SLC. If I am checking a bag I get there 60-75 minutes before hand. For the return it very much depends but in general 2-3 hours before hand because unlike the USA most all other countries have exit passport control and those lines can be longer than the security lines. The last time I arrived ~2.5 hours a head.