By most metrics, the ‘big three’ US legacy airlines (American, Delta, and United) are undoubtedly among the largest and most lucrative in the world. The trio, each of which represents a different alliance (American is in oneworld, Delta is in SkyTeam, and United is in Star Alliance), often go head to head to win passengers in important markets, with Europe being among the top targets for long-haul travel.

With this in mind, all of them are operating routes to Europe this summer that were not on their schedules last year. Looking at data made available by Cirium, an aviation analytics company, this article will compare the third quarter (July-September) of this year with the same period in 2025 to see which routes have been added. We will also examine their frequencies and their wider strategic implications.

American Airlines

Credit: Great Circle Map

Starting with American Airlines, Cirium’s scheduling data highlights six new European routes on the oneworld member’s roster this Q3. Two of them originate at Dallas/Fort Worth International Airport (DFW), with the huge Texan hub handling 34 flights to Zürich Airport (ZRH) in Switzerland in Q3, as well as another 69 to Eleftherios Venizelos International Airport (ATH) in the Greek capital city of Athens.

Elsewhere, Miami International Airport (MIA) in the US state of Florida has a new link to Milan Malpensa Airport (MXP) in Italy, while New York JFK Airport boasts Airbus A321XLR-operated flights to Edinburgh Airport (EDI) in Scotland. Both routes run daily, as do the new links from Philadelphia (PHL) to Budapest (BUD) and Prague (PRG). American’s Vice President of PHL Operations, Cesar Marchese, said that:

“We’re proud to serve as a key gateway and connection point to Europe, now with two new iconic destinations that strengthen our robust international network.”

Delta Air Lines

Credit: Great Circle Map

Delta Air Lines has gone one better than American Airlines this summer, with seven new European routes on its roster in Q3 of this year compared to the same period in 2025. Two of these originate at Seattle-Tacoma International Airport (SEA), with Delta having looked to increase its presence there following Alaska Airlines’ growth. From here, it has 53 Q3 flights to Rome (FCO) and 39 to Barcelona (BCN).

On the other side of the country, Boston Logan International Airport (BOS) in the US state of Massachusetts also has two new European routes operated by Delta Air Lines on its roster this summer. Staying with the Spanish theme, Delta will fly daily from Boston to Adolfo Suárez Madrid Barajas Airport (MAD) this Q3, as well as operating three flights a week (39 overall in Q3) to Nice (NCE) in France.

Delta’s three remaining new European routes this summer all originate at John F Kennedy International Airport (JFK) in New York City. This facility has long served as Delta’s main East Coast transatlantic gateway, and, this summer, it will operate a new daily route to Porto (OPO) from the Big Apple. JFK is also the start point for its new routes to Olbia (OLB) and Malta (MLA), with four and three weekly flights.

United Airlines

Credit: Great Circle Map

Last but not least, Chicago-based Star Alliance founding member United Airlines is operating five European routes this Q3 that were not on its roster during the same period in 2025. As seen above, all but one originate at Newark Liberty International Airport (EWR). The exception to the rule is the corridor from Washington Dulles (IAD) to Reykjavík Keflavík (KEF), which has 84 departures in the third quarter.

Of the four new additions from Newark, Glasgow Airport (GLA) in Scotland is the only corridor that will see daily service, with 92 Q3 flights. This addition is notable given Glasgow’s proximity to Edinburgh, which, as noted above, American has just started serving from JFK. United has also penciled in 29 new Q3 rotations from Newark to Split (SPU), 36 to Santiago de Compostela (SCQ), and 40 to Bari (BRI).