The second sale from Frontier in a week, this one is valid for travel to/from Denver through May 15, Mondays through Saturdays.

Avoid blackout dates: December 21-23, and December 26, through January 6, and February 14-15, and 18, and March 15-17, 22-24, and 28-31, and April 5-8.

Other carriers (United) may be matching along some routes.

Fares include:

Philadelphia to Denver $162 round-trip, nonstop, including all taxes

Orlando to Denver $162 round-trip, nonstop, including all taxes

Atlanta to Denver $166 round-trip, nonstop, including all taxes

Ft Lauderdale to Denver $158 round-trip, nonstop, including all taxes

Austin to Denver $130 round-trip, nonstop, including all taxes

Indianapolis to Denver $130 round-trip, nonstop, including all taxes

Omaha to Denver $100 round-trip, nonstop, including all taxes

Kansas City to Denver $112 round-trip, nonstop, including all taxes

St Louis to Denver $112 round-trip, nonstop, including all taxes

Frontier image via Shutterstock