Southwest customers now need only an ID and a cellphone to fly out of Baltimore-Washington International Thurgood Marshall Airport.

The airline on Thursday added Baltimore to the growing list of cities offering its Mobile Boarding Pass, which allows customers to have the passes emailed or text messaged to their smartphones in lieu of printing it out.

BWI began using the program Thursday morning, joining Austin, Chicago Midway, Dallas Love Field, Denver, Houston Hobby, Orlando and Phoenix in offering the mobile boarding option.

Southwest, based in Dallas, piloted the program in the three major Texas airports in November, and a spokeswoman said the company expects to roll it out all U.S. cities the airline flies by the end of the month.

cmcampbell@baltsun.com

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