United Airlines has announced the largest international network expansion in its history. During the 2027 summer season, the U.S. carrier will add ten new international destinations, along with several new routes to cities already served across its network. Among the additions, Ljubljana stands out, with the Slovenian capital set to gain a nonstop connection to New York, via Newark Liberty International Airport.

United will begin flying between Newark and Ljubljana on May 12, 2027, with four weekly flights operated by a Boeing 767-400ER. It will be the only nonstop service between Slovenia and the United States operated by a U.S. airline.

The announcement is particularly interesting from a Croatian perspective. United has already launched its nonstop Newark – Split service this year, operating three times per week, with the route confirmed to return for the summer 2027 season. The carrier has also been seasonally connecting Newark and Dubrovnik for several years, meaning that with the addition of Ljubljana, United will have effectively surrounded Zagreb – the only major capital in this part of the region still without a nonstop United connection to the United States.

Moreover, as United continues expanding its network to smaller and tourism-focused European markets, the prospects of a Zagreb route appear increasingly uncertain. From 2027, passengers from the wider Zagreb area will have access to United’s nonstop flights from Ljubljana, while Split and Dubrovnik will provide additional seasonal alternatives. As a result, part of the potential demand that Zagreb could otherwise consolidate is increasingly being captured by surrounding airports.

United’s strategy in recent years has focused heavily on launching routes to destinations that are largely unserved by its U.S. competitors. Since 2017, the carrier has added 58 international destinations to its network and today serves more than 160 destinations outside the United States. Eight of the ten new cities announced for 2027 will not have nonstop service from another U.S. airline.

Alongside Ljubljana, most of United’s new European routes will operate from its Newark hub. Luxembourg will receive daily Airbus A321XLR flights beginning April 2, while Ljubljana will follow on May 12. From May 27, United will fly three times weekly to Olbia in Sardinia with a Boeing 767-300ER, followed a day later by four weekly flights to Catania, Sicily, using the same aircraft type.

Ibiza will be served four times weekly from May 31, Valencia three times weekly from June 2, and Marseille daily from June 4. All three routes, as well as the Luxembourg service, will be operated with the Airbus A321XLR. Terceira in the Azores will receive three weekly Boeing 737 MAX 8 flights beginning June 9.

Outside Newark, United will launch a San Francisco – Okinawa route on March 27, operating three times weekly with a Boeing 777-200ER. Washington Dulles and Toulouse will be connected daily from April 26 with the Airbus A321XLR. The airline is also expanding service to existing destinations, with Los Angeles gaining a daily Osaka flight, Washington receiving three weekly flights to Milan, and Denver gaining daily service to Paris. United also plans to resume flights between San Francisco and Tel Aviv.

The Airbus A321XLR will play an important role in the next phase of United’s international expansion, with the airline describing the aircraft as its new international jet “Born to Explore.” United’s configuration will feature 20 United Polaris suites with fully flat beds, 12 United Premium Plus seats, complimentary Starlink connectivity for MileagePlus members and 4K OLED displays. International A321XLR operations are expected to begin on December 1, 2026, with services from Washington to Amsterdam and Dublin.

For Croatia, United’s confirmation that Split will return in summer 2027 is particularly significant. The first nonstop Newark – Split flight was launched on April 30 this year, making Split United’s second destination in Croatia after Dubrovnik. The Croatian National Tourist Board previously noted that U.S. visitors recorded more than 850,000 arrivals and 2.4 million overnight stays in Croatia during 2025.

Zagreb, however, has once again failed to find a place on United’s route map. After Dubrovnik and Split, Ljubljana – less than two hours’ drive from Zagreb – will now join the list of nearby airports with a direct United connection to the United States. As the airline systematically fills in its Central and Southeast European network with nonstop services from Newark, the commercial space for a separate Zagreb route is becoming increasingly narrow.