The latest sale from Southwest includes both domestic and international routes for nonstop travel through spring 2018.
Fares are valid for nonstop travel on Mondays through Thursdays, as well as Saturdays, from December 19 through May 23. Fares to/from San Juan, Puerto Rico are valid from January 16 through March 1, and again from April 3 through May 17. International fares are valid for travel from January 9 through March 1, and again from April 3 through May 18.
Avoid black out dates from December 22-23, December 26-27, and December 30.
Tickets must be booked by 11:59pm, December 7.
Please note, these fares are only available on Southwest.com. Other carriers regularly match these sale fares, so be sure to compare to find the best deal.