BOSTON (CBS/AP) – Southwest Airlines plans to stop overbooking flights. That announcement was made Thursday by Southwest Airlines CEO Gary Kelly.

Last year Southwest bumped 15,000 passengers off flights, more than any other U.S. airline. Carriers say they sometimes sell more tickets than there are seats because of frequent passenger “no-shows.”

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The practice of overbooking flights has come under intense public criticism since April 9, when a passenger was dragged off an overbooked United Express plane after refusing to give up his seat for a crew member.

That incident prompted the city of Cambridge, MA to pass a resolution banning its public employees from using United Airlines.

Southwest CEO Gary Kelly said Thursday that the airline had been thinking about ending overbooking for “a long time” because of fewer and fewer no-shows. But the issue gained more urgency after the United incident, he said.

Beth Harbin, a Southwest spokeswoman, said Thursday that with better forecasting tools and a new reservations system coming online next month the airline will no longer have a need to overbook flights.

Politicians in Washington and elsewhere have called for a ban on overselling flights. Some critics have said airlines should leave a few seats empty if they think they will be needed by crew members.

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JetBlue is currently the only major U.S. airline with a stated policy that bans overbooking. United said Thursday that it plans to reduce overbooking but not eliminate it entirely.

Dallas-based Southwest did not say when the policy would become effective. Kelly noted that Southwest may still need to bump people if, for instance, the airline substitutes a smaller plane for the one originally scheduled, which happens occasionally.

Kelly was asked on an earnings conference call if the move could impact Southwest’s results. He said ending overbooking would have a minor impact on revenue but gave no figures.

Chief Financial Officer Tammy Romo said doing away with overbooking would save the airline money because airlines have to compensate the passengers for giving up their seats. She also says the savings from not having to pay a passenger will offset any losses the airlines sees from overbooking.

Southwest Airlines serves Boston’s Logan Airport, Manchester-Boston Regional Airport in Manchester, NH, and Providence, Rhode Island’s T. F. Green Airport.

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