Why Plane Tickets Are Suddenly So Cheap

A big Southwest Airlines sale is driving its competitors to try to match its cheap prices, with fares for many flights dropping below $100.

Southwest’s semi-annual sale began on Tuesday, and by Wednesday morning, rivals like American Airlines, Delta and United had selectively matched a number of Southwest’s cheap prices, USA Today reports. The big discounts are most notable on flights of relatively short distances. Among the matched routes are Los Angeles to San Francisco, Houston to Dallas, Baltimore to Boston and Minneapolis to Chicago.

Travelers looking to capitalize on the sale have until 11:59 p.m. on Thursday before Southwest’s sale ends.

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