1 DAY ONLY: Frontier Airlines is selling $20 flights today

Want a cheap flight? You'll need to act fast! Frontier Airlines is offering $20 flights to and from select cities including Houston, but you only have a few more hours to buy your ticket since the flights must be booked no later than Thursday.

Travelers can snag $20 Frontier Airlines tickets on routes all over the country including Houston to Atlanta, Dallas to Cincinnati and San Antonio to Denver.

There are some restrictions. Frontier's $20 flights are valid for travel on Tuesdays, Wednesdays, and Saturdays from August 15 to October 4. There is one blackout date: September 5 (the Tuesday after Labor Day.)

If you do plan to fly Frontier, remember the airline is very similar to Spirit Airlines and customers face fees for almost any amenity above basic transportation, which includes baggage and seat arrangements.

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