i got an email from amex
Get 10% off your next Frontier flight to
80+ cities in the U.S., Mexico & Costa Rica.
With more than 80 destinations across the U.S., Mexico and Costa Rica, how will you choose? Use your American Express® Card at FrontierAirlines.com and every passenger in your itinerary gets 10% off our already great low fares. Book your ticket August 16-30, 2011 and travel August 23, 2011 through March 18, 2012. Simply use Promo Code AXMKT when booking to receive the discount. Some blackout dates apply. See terms & conditions for details.
but i cant find anywhere on frontiers site to put in the promo code
