It's a week of deals from Southwest Airlines, including up to 50% off flights and up to 30% off car rentals, plus extra Rapid Rewards points when you book those rentals through Southwest.

"We understand flexibility and great deals are top of mind for customers looking to book their next trip," Jonathan Clarkson, vice president of marketing at Southwest Airlines said in a statement. 

Breeze Airways and Frontier Airlines are also offering discounts this week, with 25% and 90% off flights, respectively, for those who act fast. 

These deals pretty much always come with fine print, and here's what to know before you book for each of them. 

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Southwest's Week of Wow

If you book travel on Southwest Airlines by 11:59 p.m. PT on Thursday, you could get up to 50% off your flights with the code WOW50.

The deal is valid on Wanna Get Away and Wanna Get Away Plus fares for flights between Oct. 24 and March 6.

For travel within the Continental U.S., Nov. 17-22 and 25-27, Dec. 21-23 and 26-30, Jan. 1, 2, 6 and 7 and Feb. 16 and 19 are Blackout Dates. 

Orange County (SNA) is additionally blacked out through Jan 2.

Blackout dates to international destinations, as well as those in Hawaii and Puerto Rico, are Nov. 17-19, Dec. 15 - Jan. 8, Jan. 11-13 and Feb. 15-18.

Blackout dates from international destinations, as well as those in Hawaii and Puerto Rico, are Nov. 24-27, Dec. 15-Jan. 8, Jan 15 and 16 and Feb. 23-27. 

Full terms of the sale, including more information about discounted car rentals are available on Southwest's website by clicking here.

You do not need to be enrolled in Rapid Rewards to take advantage of the discounts, but you do need to be a member to receive the points from the car rental deal.

Breeze's 25% off sale

Travelers who book through Thursday for flights by Jan. 31 can get 25% off Breeze base fares using the promo code SOEXTRA. 

Press materials say certain days or flights may not be available, but the airline has not specified the blackout dates for this sale.

In addition, travelers who purchase tickets under the promo will be eligible for 5,000 BreezePoints, worth $50 toward their next flight, so long as they're enrolled in the program and the original value of the flights is at least $150.

Frontier's 90% off sale

Frontier is offering 90% off flights on Tuesdays, Wednesdays and Saturdays so long as you book by the end of the day Tuesday, Sept. 26 and fly by Dec. 15.

To take advantage, use the promo code SAVE90. Nov. 18-28 are blackout dates for this deal. 

In addition, travelers who purchase tickets under the promo will be eligible for 5,000 bonus miles after completing their trip, so long as they're enrolled in the Frontier Miles program. 

Full terms can be seen on Frontier's website by clicking here. 

Zach Wichter is a travel reporter based in New York. You can reach him at [email protected].