They charge per flight, it depends on the schedules lenght of the flight.

***don't hold me two the actual $$'s but I am pretty sure I am in the neighborhood:

Something like 5.00-6.00 for flights up to 2-3 hours, and 7.00-9.00 for flights 3-5hrs.


Also, you can save like 2.00 off a flight if you pay with a CO chase card.