The 4 percent increase instituted this weekend had been in doubt for several days. Continental moved first to raise fares on Friday. But by Monday, several airlines rolled back the increase while Northwest's position was unknown. Later Monday, American Airlines and U.S. Airways Inc. had once again upped their prices. Passengers traveling for pleasure typically buy the leisure-fare tickets, which come with restrictions such as advance purchase requirements.
Fares are lower if purchased further in advance.
Delta spokeswoman Sarah Anthony said the increases are only for leisure fares at this point, although business fares have seen industrywide increases of 3 percent so far this year. The demand for seats has been a major reason behind the higher prices. Continental spokesman Ned Walker said the increased fares reflect strong demand. Ms. Anthony agrees. Still, overcapacity at the airlines is expected to be a problem this year with the number of available seats rising by 5.6 percent in this quarter alone, according to analyst Susan Donofrio of BT Alex. Brown.