Delta Air Lines Inc., taking a page out of loyalty programs offered by smaller U.S. carriers, said it would revamp its SkyMiles frequent-flier plan starting Jan. 1.

Delta Air Lines on Wednesday said it will make a major change to its frequent-flier program, basing rewards on money spent rather than miles flown, a model already used by discount airlines and one that major competitors might copy.

The change, which will take effect next year, will sweeten mileage awards for travelers who pay more for airline tickets, the carrier said in a statement. But some travel experts are uncertain the program will be better than the existing one, for business or leisure fliers.

Years ago, fares correlated more closely with miles traveled, so miles were a good gauge for money spent with the airline. That's no longer true. Flights of the same number of miles could cost $200 or $1,000. 

Atlanta-based Delta said the new program would favor "frequent business travelers" and leisure fliers who buy tickets at higher fares.


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Passengers will garner between 5 and 11 miles for each dollar spent on airfares depending on their frequent-flier status, with those at the highest level earning the most, the carrier said.

"The travel industry, including nearly all hotel and credit card programs, has already moved to a spend-based model," Jeff Robertson, vice president for Delta's SkyMiles loyalty program, said in the statement. "Delta will become the first U.S. global carrier to make this transition to better reward our most loyal customers."

A United Airlines spokesman declined to say Wednesday whether the Chicago-based airline would make a similar move. 

But starting Jan. 1, United took its own step to reward bigger spenders. It now requires frequent fliers to spend minimum amounts to achieve elite flier status, in addition to flying a certain number of miles or segments. 

For example, those who want to achieve the lowest elite tier of the MileagePlus program, called Premier Silver, will have to fly 25,000 miles or 30 segments, but also spend a minimum of $2,500 on United tickets. 

United followed Delta in making that change in requirements for elite status.

George Hamlin, an aviation consultant in Fairfax, Va., said the frequent-flier plan change comes as airlines look to cater more to most profitable customers. Corporate customers can spend two to three times or more than leisure passengers, who tend to look for bargains. Business travelers also tend to book more flights.

"It's going to upset a lot of people but it's economic reality," Hamlin said. "Leisure passengers typically seek out price, and carrier loyalty is often a second priority."

JetBlue Airways and Southwest Airlines also tie frequent-flier miles earned to the amount spent on a ticket, and Hamlin said he expects other major U.S. airlines to follow suit.

Delta's change is a big move, and it makes sense to move to a revenue-based program, but missing in Wednesday's announcement is how earned miles can be spent, noted Joe Brancatelli, a business-travel writer and editor of JoeSentMe.com.

Preliminary indications are that it would cost more SkyMiles than before to get the same flights for some elite levels, he said.

"I see no positives here right now ... I don't understand the incomplete rollout," he said. "We have no way to figure out what this means in totality."

Brian Kelly, founder of ThePointsGuy.com, wrote Wednesday that he will wait to judge the new Delta program until more details are released, "but basically this will be horrible for most consumers, except those who pay exorbitant amounts for their flights may see a slight increase," he wrote. "This is actually just another slash to a program that has been decaying for years."

American Airlines Group declined to comment on Delta's move or any possible changes to its program.

American, newly combined with US Airways, must revamp its frequent-flier program anyway because of the merger and could be the next major carrier to move to a revenue-based program, Brancatelli said.

He said United seriously considered it after its 2010 combination with Continental Airlines, but in the end decided to implement a traditional miles-based program.

gkarp@tribune.com