Discount carriers Southwest, AirTran and Frontier touched off a round of fare sales with prices below $100 on many shorter routes.
Most other carriers quickly matched the sale prices Tuesday, which cover a limited number of seats and must be purchased in the next couple days.
The moves marked an early start to the usual discounting of travel during the weak fall season, and came after a couple recent fare hikes for summer travel. In the last few days, airlines have reported that traffic fell again in June, and they cut flights — and as a result, the supply of seats — to shore up prices.
On Tuesday, Dallas-based Southwest Airlines Co. announced a two-day sale with fares of $30 each way on flights of 400 miles or less, including one of its newest legs, between New York's LaGuardia Airport and Baltimore. It also offered $60 one-way fares for flights between 401 and 750 miles and $90 one-way for longer trips.
Seats at those prices for travel between Sept. 9 and Nov. 18 were limited, however, and weren't offered at all on Fridays and Sundays.
"They're leaving Fridays open for the business travelers so they can charge them a little more," said Tom Parsons, CEO of travel Web site Bestfares.com. He said most other airlines, including giants American, Delta and United, had matched prices on routes where they compete with Southwest.
AirTran Airways offered fares as low as $39 each way for some short hauls from mid-July through Nov. 11, with the lowest prices on Tuesdays, Wednesdays and Saturdays. Tickets must be purchased by Thursday.
The airline, a unit of Atlanta-based AirTran Holdings Inc., cited a sample fare of $69 each way between Atlanta and Boston.
Frontier's sale covers travel from Aug. 10 through Jan. 15, with a deadline of next Tuesday for buying tickets. There are blackout dates around the December holidays, but the sale's unusual length could make it appealing to skiers.
Rick Seaney, CEO of FareCompare.com, said such widespread sales had nearly disappeared over the past several weeks after nearly six months of constant discounting by all U.S. airlines.
"That dry spell ends today," he said.