The nation's major airlines have matched a fare increase of up to $30 per round trip that was started by United Airlines.
American Airlines, the nation's largest carrier, matched the fare hike on Friday afternoon, which may have removed the last obstacle to making the increase stick.
Airlines say they need to raise fares to cover jet fuel costs. The price of fuel tracks the price of oil, which hit a record Wednesday before declining Thursday and Friday.
Delta Air Lines Inc., Continental Airlines Inc., Northwest Airlines Corp., and US Airways also matched the United increases of $4 to $30 for round-trip tickets.
Some of the carriers and people who track fares said the increases added $10 per round trip on flights up to 500 miles each way; $20 on flights from 501 to 1,500 miles each way and $30 for transcontinental flights.
Rick Seaney, chief executive of travel Web site FareCompare.com, said it was the carriers' 11th attempted fare hike this year. Six of the previous increases stuck, and Seaney said the quick matching by all the network carriers made it likely the new one would hold too.
Fare hikes fail if one or more carriers balk, and occasionally airlines roll them back in the first few days.
American is a unit of AMR Corp.; United, the nation's second-largest carrier, is part of UAL Corp., and US Airways is part of US Airways Group Inc.