Most other airlines have matched a price increase by Southwest Airlines Co., meaning that travelers could pay $10 per round trip more for shorter trips.

The fare hike, which started Friday, applied to flights of less than 500 miles each way. It was matched by others including United, Delta and American.

J.P. Morgan analyst Jamie Baker considered the increase a variation of a United-led fare hike in July that was partly rolled back when Southwest refused to raise short-haul flights.

Baker predicted that airlines will keep trying to raise prices because of high fuel prices and a limited supply of seats.

The Dallas carrier attributed the increase to higher costs. Its second-quarter operating expenses rose 6 percent including increases for fuel, labor and maintenance.