Southwest Airlines Co. said Friday that it would keep Portland and 21 other cities served by AirTran Airways on its flight schedule but end flights to six others – raising the final cut list to 15 AirTran locations – as it combines the two airlines.

The dropped cities are smaller than typical Southwest markets and include Allentown, Pa., and Sarasota, Fla. Southwest said it couldn’t afford to serve such markets with today’s high jet fuel prices.

The decision ended months of suspense after Southwest bought AirTran in May. AirTran served 69 cities, including many also served by Southwest.

Southwest and AirTran operate as separate airlines, but Southwest intends to combine the two starting this year. AirTran employees in the 22 surviving cities will eventually wear Southwest uniforms, although the switch could take several years.

Southwest announced Friday that on Aug. 12, AirTran will pull out of Allentown and Harrisburg, Pa.; Lexington, Ky.; Sarasota, Fla.; Huntsville, Ala.; and White Plains, N.Y.

The Dallas-based company had previously said that it would halt AirTran service at Miami; Knoxville, Tenn.; Asheville, N.C.; Atlantic City, N.J.; Bloomington and Moline, Ill.; Charleston, W.V.; and Newport News, Va.

AirTran ended flights at Dallas-Fort Worth International Airport in November – Southwest flies out of nearby Dallas Love Field. AirTran will also depart Dulles Airport outside Washington, but Southwest flies there.

The changes announced Friday will be included in new schedules that Southwest and AirTran will publish Sunday.

In addition to Portland, the U.S. cities served by AirTran that will eventually switch to Southwest service are Flint and Grand Rapids, Mich.; Rochester, N.Y.; Pensacola and Key West, Fla.; Charlotte, N.C.; Dayton, Ohio; Richmond, Va.; Reagan National Airport near Washington, D.C.; Memphis, Tenn.; Akron-Canton, Ohio; Wichita, Kan.; Des Moines, Iowa; and Branson, Mo.