Take $20 off your next round-trip flight on Frontier ($10 off each way). Just enter promo code PLAYBALL when booking at FlyFrontier.com. Travel is valid between April 14 and June 11, 2015.

Blackout dates of May 22, 23, & 25, 2015 apply and the promo code is not valid for Friday/Sunday travel. As always with Frontier's fares, keep in mind that they charge a $25 fee each way for carry-on bags larger than 18 x 14 x 8 inches so travel super light or compare their checked bag fees with other airlines if you plan on checking a bag anyway. This promo code expires at 11:59 p.m. eastern time on April 10, 2015.

Sample fares include:

Cincinatti to Fort Lauderdale $58 round-trip, nonstop

Philadelphia to Tampa $98 round-trip, nonstop

Denver to Atlanta $98 round-trip, nonstop

Denver to Minneapolis/St. Paul $86 round-trip, nonstop

Denver to Las Vegas $38 round-trip, nonstop

Atlanta to Indianapolis $48 round-trip, nonstop

Washington D.C. to Cincinnati $44 round-trip, nonstop

Washington D.C. to Miami $58 round-trip, nonstop

Denver to San Diego $78 round-trip, nonstop

Atlanta to New York $158 round-trip, nonstop

Chicago to Denver $78 round-trip, nonstop

Minneapolis/St. Paul to Atlanta $78 round-trip, nonstop

Frontier image via Shutterstock.