MileValue is part of an affiliate sales network and receives compensation for sending traffic to partner sites, such as This compensation may impact how and where links appear on this site. This site does not include all financial companies or all available financial offers. Terms apply to American Express benefits and offers. Enrollment may be required for select American Express benefits and offers. Visit to learn more.

Note: Some of the offers mentioned below may have changed or are no longer be available. You can view current offers here.

Frontier and Southwest have put domestic flights on sale for a limited time. The Frontier sale lasts through the end of today (11:59 pm ET) and is good for travel dates through November 16, 017. The Southwest sale lasts through September 28 at 11:59 pm in the time zone of the origin of your flight and is good for travel October 17, 2017 through May 23 of 2018.

Frontier 90% Off (the Base Fare) Sale

To the apply the discount, input FALL90 in the coupon code box at checkout.

While the sale is advertised as 90% off, it’s actually 90% off the base fare–there’s no discount on taxes & fees. In many circumstances however this still represents a great deal of savings.

Take this one-way flight from Atlanta to Denver, which costs $84 before entering the Promo Code…

…and $39 after.

Wondering what DENDEAL$ are? They’re discounted fares for members of Frontier’s Discount Den, which costs $50 a year to join. Read more in Should You Join the Frontier Discount Den or Spirit $9 Fare Club?

Other Important Terms

  • Non-stop flights only
  • Only good for flights on Mondays, Tuesdays, Wednesdays, Thursdays, and Saturdays
  • Ticket must be purchased at least three days in advance of your flight
  • There are various routes the sale doesn’t apply to from Atlanta, Cleveland, Denver, Cincinnati, Orlando and other cities. Read the full list of excluded routes here.

Frontier Hub and Focus Cities

Denver is Frontier’s only hub. The rest are focus cities.

  • Denver
  • Atlanta
  • Chicago
  • Cincinnati
  • Cleveland
  • Las Vegas
  • Orlando
  • Philadelphia
  • Trenton

For Future Notice…Pay Less for Frontier Tickets at the Airport

One Mile at a Time wrote about saving money by buying Frontier tickets at the actual airport to avoid the surcharge the airline collects for using their website. If you live close to an airport and are buying tickets for a family, it could actually be worth your time to make a trip.

Southwest Sale

Southwest has put many routes on sale during the travel period between October 17, 2017 and May 23, 2018. You can pay cash or Rapid Reward points for these flights.

Other Important Terms

  • Non-stop flights only
  • Ticket must be purchased at least 21 days in advance of your flight
  • Domestic sale flights not valid on Fridays or Sundays
  • Tickets are non-refundable

Southwest Operating Bases and Focus Cities

Operating Bases are in bold. The rest are focus cities.

  • Phoenix
  • Oakland
  • Denver
  • Orlando
  • Atlanta
  • Chicago
  • Baltimore
  • Las Vegas 
  • Dallas 
  • Houston
  • Los Angeles
  • Sacramento
  • San Diego
  • San Jose
  • Fort Lauderdale
  • Tampa
  • St. Louis
  • Nashville

Bottom Line

Through tonight at 11:59 pm ET you can buy select one ways on Frontier for 90% off the base fare, good for travel through November 16, 2017. Through 11:59 pm in the time zone of your origin you can buy discounted Southwest tickets for as low as $29, good for travel through May of 2018.

If you’re planning domestic travel to/from cities served by Frontier and/or Southwest, it’s worth checking out their fares for your desired travel dates.