Today only, Frontier Airlines offers last minute 1-way fares on select 53 routes nationwide with prices starting at $19. (Click on "Frontier Airlines" in the top line to see this sale.) That's $20 under last week's mention and second-best price we've seen for fares on Frontier Airlines. It's also the lowest price we could find for select flights by $21. This price is valid on flights departing from Denver, CO, (DEN) with arrival in Las Vegas, NV, (LAS) on May 5. Book this travel deal today for travel from May 5 through May 30. Click here to see more routes.