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Southwest fares drop below $100 round trip in 72-hour sale

Southwest rolled out a 72-hour, nationwide fare sale Tuesday (June 2) in which the price of its flights are roughly based to distance. Dozens of the carrier's shortest routes are available for fares of less than $100 round trip.

The sale covers travel from Aug. 25 through Dec. 16, though some holiday periods are blacked out. And bargain hunters must act quick; the sale concludes at the end of the day Thursday (June 4).

Southwest has previously rolled out similar fare sales in which fares were pegged to mileage thresholds. In past years, for example, Southwest 's sales priced flights of 500 miles or less at $49 each way and increased from there. Flights of 501 to 1,000 miles cost $99 each way and flights of 1,001 to 1,500 miles cost $129 each way. Flights of more than 1,500 miles went for $149 each way.

File photo of Southwest Airlines planes
Getty Images
File photo of Southwest Airlines planes

While Southwest may have officially ended the precise mileage component of its big sales, this latest promotion appears to closely mimic those previous distance-based promotions. The carrier's four advertised sale-fare tiers—$49, $99, $129 and $149 each way—match the fares it offered on its distance-based sales of years past.

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Whatever the details, travelers can snag advertised round-trip fares as low as $98 on short routes. Many routes, such as Chicago-Minneapolis, Los Angeles-San Francisco and Atlanta-Richmond, Va., showed fares as low as $98 (including taxes). Fares on longer flights appear to increase incrementally roughly in correlation to the distance flown.

But the scope of this Southwest sale appears to be more limited than its previous similar promotions. Some of the carrier's sub-500-mile routes – such as Atlanta-New Orleans, Baltimore-Charleston, S.C., and Denver-Albuquerque – were not being sold for the lowest $49 fares. Instead fares on those routes – and a number of Southwest's other short routes – were going for higher sale fares of $63 to $73 each way.

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On the flip side, a small number of Southwest's other short routes – such as Chicago-Memphis and Denver-Omaha – were available for even less. Those routes were selling for just $44 each way. Five routes from California's Ontario airport were selling for $46 each way, including Las Vegas, Oakland and Phoenix.

Regardless of the fare and distance, deal-seekers will have to move fast to lock in those prices. Southwest's sale runs only through the end of the day Thursday (June 4), and the cheapest fares will disappear as they sell out.

For the short routes that are priced at $49 each way, that makes for round-trip fares of less than $100 on many city-pairs.

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Among the sub-$100 options: Boston-Baltimore; Burbank, Calif.-Sacramento; Charlotte-Baltimore; Cleveland-Chicago Midway; Columbus, Ohio-Washington National; Dallas Love-New Orleans; Denver-Omaha; Detroit-Chicago Midway; Houston Hobby-Corpus Christi, Texas; El Paso-Austin; Grand Rapids, Mich.-St. Louis; Indianapolis-Kansas City; Las Vegas-San Diego; Los Angeles-Oakland; Memphis-Houston Hobby; Nashville-Pensacola, Fla.; New York LaGuardia-Akron/Canton, Ohio; Pittsburgh-Chicago Midway; San Jose, Calif.-Orange County, Calif.; San Francisco-Los Angeles and Spokane, Wash.-Boise.

Southwest's fares are blacked out around Labor Day (Sept. 3-5 and Sept. 7 are excluded) and around Thanksgiving (Nov. 2- through Dec. 1 are excluded). The lowest fares are not offered on Fridays and Sundays. Additionally, the days that the sale fares are offered are further restricted to Southwest's destinations in Florida, Nevada and Puerto Rico. The cheapest sale fares will disappear from flights on all routes as those fares begin to sell out.

Tickets must be purchased Thursday by 11:59 p.m. in the time zone of the originating city.