ravelers often say that the big airlines are as responsive to their complaints as a block of concrete. But this week, some airlines are rolling back to a degree a stringent use-it-or-lose-it policy on nonrefundable tickets that they put in place last fall to nudge business travelers toward buying higher-priced refundable tickets.

On Tuesday, American Airlines, the world's largest carrier, said it would allow a passenger to apply the full value of a nonrefundable ticket to a future ticket if the passenger called in to cancel a flight before the plane's departure. The passenger will have one year from the date the original ticket was issued to apply the value of the ticket to the new flight. The passenger will also have to pay a change fee that usually amounts to $100 for domestic flights and up to $200 for international flights.

Continental Airlines followed American's lead on Wednesday. Delta Air Lines said yesterday morning that it was also adopting the policy. Northwest Airlines went one step further and said yesterday that travelers could still keep the value of their original ticket for a year from the departure date even if they did not call in advance to cancel a flight.

The new policy is more generous than one that the airlines had put in place in the fall of 2002. Under those rules, passengers canceling a flight had to book a new flight by the departure date of their original flight or they lost the value of the ticket.

Except for Northwest, the policy being adopted this week is not nearly as consumer-friendly as one that was in place before the fall of 2002. Under the old rule, passengers could retain the value of their nonrefundable ticket for a year even if they did not call in to cancel a flight.

When the airlines went from that lenient policy to the hard-edged one, they were flooded with complaints, especially from business travelers.

Tim Wagner, a spokesman for American Airlines, a unit of the AMR Corporation, said the company received complaints "frequently." He said passengers canceling flights often did not know when they would travel next and chafed at the fact that they were required to book another flight before the original departure date.

As of mid-afternoon yesterday, two major airlines had not followed American, Continental, Northwest and Delta. The holdouts were US Airways, the carrier that first announced the use-it-or-lose-it policy, and its code-sharing partner, United Airlines, a unit of UAL, which said it had no plans to match the new refund policies. In August 2002, the same month it filed for bankruptcy protection, US Airways said it was imposing the stringent policy on tickets for travel starting in the fall. The other major hub-and-spoke airlines quickly matched its move.

During the economic slump, business travelers have been turning away from buying expensive, last-minute tickets and gravitating toward nonrefundable tickets with greater restrictions and change fees. The imposition of the tougher policies last fall was intended to discourage business travelers from buying the cheaper tickets, though there are no signs that has worked.

Airlines have been sharply cutting back on passenger service since the recent economic slump and the attacks of Sept. 11, 2001. They have tried eliminating hot meals on domestic flights, charging travelers to fly standby and charging for overweight or oversized baggage that would have been loaded on the plane free a couple of years ago. The new standby fees were watered down or eliminated when passengers and consumer advocates railed against the airlines.

The constant changing of consumer policies has become one of the greatest indicators of the increasing desperation of the airlines as they struggle to make a profit during the industry's worst financial downturn.

"We're rearranging deck chairs on the Titanic," said Joe Brancatelli, an Internet travel columnist and advocate for business travelers. "This is what the airlines always do."

Mr. Brancatelli said the confusion of the airlines over how to treat nonrefundable tickets pointed to a larger problem with the fare structure. Airlines should treat tickets and seats as if they are commodities that passengers own once they are bought, he said. This means that travelers would be able to do anything they want with the tickets once they are bought, including reselling them or giving them away. It also means passengers would not get to reapply the value of their tickets to a future flight if they cancel their original flight.

Theaters and sports stadiums operate on that model, he said, so why not airlines?