By Alison Sider

Chicago is at the center of an airline brawl.

United Airlines and American Airlines are battling for the hearts and wallets of travelers coming through O'Hare International Airport. At the fourth-busiest U.S. airport, the carriers are marketing splashy new destinations, debuting their fanciest new planes and refreshing amenities for customers.

American is turning up the heat. This month, it sued the city of Chicago to halt a plan that would award United more gates at the airport and reduce American's footprint.

"United's long-term plan for O'Hare envisions no place for American," the airline wrote in its complaint. American said its presence at O'Hare means more flights and lower fares.

The city's law department declined to comment, citing pending litigation.

United, which has its headquarters in Chicago and bills itself as the city's hometown airline, has been steadily expanding its O'Hare schedule.

American is also amping up its flights from O'Hare. This summer, the airline will fly 20% more seats from the airport than it did last year, according to data from Cirium.

The fight is raging outside the airport, too. A huge sign greeting cars driving up to O'Hare points toward "Chicago's #1 Airline" at United's terminals, and "The Rest" farther ahead.

American has draped buildings with ads touting premium seats and new destinations like Naples, Italy, which United doesn't fly to nonstop from O'Hare.

The showdown hits when travel demand is wavering, and many airlines are planning to cut flight schedules. With two major airlines claiming O'Hare as a major hub, and Southwest dominating Midway International Airport across town, neither can afford to ease up.

It's not clear whether the battle will lower fares for all O'Hare travelers but there are signs of some price relief at airports. Airfares for domestic trips this summer from O'Hare cost $386 on average, down 3% from last year, according to data from Kayak.

There are other signs travelers might be a big winner. American plans to add new flights later this year to vacation spots in the Caribbean and Central America. Its newly delivered Boeing 787 Dreamliners with sliding-door, business-class suites will start flying from Chicago this summer.

United recently reopened an O'Hare international business-class lounge that is 50% bigger than it was before. The airline said it has pulled far ahead of American at O'Hare, with about 100 more daily flights this summer and more international destinations.

"Market share became available, and we seized it," United Chief Commercial Officer Andrew Nocella said in an interview.

Such battles have become less frequent as airlines have invested in giant hubs and created competitive moats. For Chicago, which has had corporations such as Boeing and Caterpillar relocate their headquarters from the area, the extra attention from large airlines is welcome.

"It's actually kind of exciting," said Joseph Schwieterman, a professor at DePaul University's School of Public Service. "Other hubs seemed to be winning the battle...Now we have a situation where they both want to expand in short order."

American has said it always intended to bulk back up in Chicago, but "it's all been logistical constraints that have kept us from doing that, " said Brian Znotins, the airline's senior vice president of network planning.

After the pandemic, with shortages of planes and pilots, it focused on rebuilding service in fast-growing hubs such as Miami, Dallas and Charlotte, N.C. A failed attempt to overhaul how it competes for business travel led it to pull back on routes such as Chicago to New York.

Now, American is adding seats this year in more than 100 markets where it overlaps with United, according to an analysis by Airline Data.

Travel agents in the region cheered the intensifying rivalry.

"We view this as a positive development that will enhance specific travel options and pricing for the Chicago market," said Alex Holmberg, director of operations of Foremost Travel Group in Chicago.

In American's suit, filed in federal court in Illinois, it argued that United maneuvered to squeeze it out and prematurely claim more gates at O'Hare.

United asked the city to re-evaluate how much gate space each carrier should get. Under a process outlined in a lease agreement, that decision is based on each airline's flight statistics from the previous year.

United is set to pick up six gates under the city's reallocation plan. Nocella said the change will allow the airline to offer year-round service to two international destinations it currently only flies to seasonally.

American, on the other hand, could lose space, which it said would thwart its growth plans. It maintains that under the terms of the lease agreement, the reallocation process can't start until 2027, after it has had time to make full use of some newly constructed gates.

The Chicago Department of Aviation, which oversees O'Hare, has said it believes the conditions to redetermine gates were met.

United in a court filing countered that American has only itself to blame for losing ground in Chicago. In a message to employees, United President Brett Hart said the airline is prepared to fight any effort to obstruct its growth.

"It's clear that American has been neglecting Chicago for years," the message said.

Write to Alison Sider at alison.sider@wsj.com

(END) Dow Jones Newswires

May 11, 2025 05:30 ET (09:30 GMT)

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