Save at least $5 on over 65 routes nationwide. Buy Now at DealBase Tips On the DealBase landing page, click "Frontier Airlines" in the top line to see this sale. We found this price on flights departing from Albuquerque, NM (ABQ) with arrival in Denver, CO (DEN) on February 20. Book this travel deal by January 3 for travel from January 7 through March 5. All prices, dates, and booking details were valid at the time of publication.