Southwest Airlines will return a pair of weekend flight slots at Washington National airport to US authorities, after winning them as part of a bundle in an auction of slots divested by American Airlines.

The Dallas-based carrier had won a majority of the auction of 44 slot pairs auctioned by American, netting 28 slot pairs. But it will utilise only 27. “Our winning bundle did include a pair of Sunday only slots which we do not intend to utilise,” the airline tells Flightglobal.

A Southwest spokesman confirms that the Sunday slot pair will be returned to the US federal government. Southwest had earlier announced it had won 27 slot pairs, while JetBlue won 12 and Virgin America secured four, totalling 43 slot pairs. This had left a slot pair unaccounted for, which Southwest now confirms it had won.

The airlines have yet to announce where they will fly to with their new slots, which were divested by American as a condition imposed upon it for approval of its merger with US Airways.

Source: Cirium Dashboard