United Airlines is the largest long-haul operator serving the US. In 2025, the Star Alliance member had 20.9 million such passengers, which was its best year to date. Traffic rose by a healthy 6.6% compared to the prior high, which was in 2024.
Some context is needed. Given United’s vast scale, long-haul passengers only represented 11.5% of its total traffic. Nonetheless, that was double the proportion for American Airlines and was three percentage points greater than for Delta Air Lines. All of this data was from the US Department of Transportation.
United’s Ten Long-Haul Routes With The Lowest Load Factors
The DOT shows that United’s average long-haul load factor was a relatively low 81.0% last year. This is based on examining all routes above 2,650 nautical miles (3,050 statute miles, 4,908 km) with at least 2,500 round-trip passengers.
Any analysis of load factors comes with caveats, which have been discussed many times before. Some other context is usually also required. That’s no different here. Many of the following routes have already ended or started/returned at some point last year. One even began in December 2025.
|
Seat Load Factor In Full Year 2025* |
International Route** |
Round-Trip Traffic*** |
|---|---|---|
|
52.3% |
San Francisco-Panama City |
38,851 (new route: started in May 2025, but ended in January 2026) |
|
55.8% |
Washington Dulles-Dakar |
21,946 (new route: started in May 2025, but ended in January 2026; yes, two in a row) |
|
61.6% |
Newark-Tenerife South |
11,493 (route ended in May 2025) |
|
63.8% |
Los Angeles-London Heathrow |
119,884 |
|
67.2% |
Los Angeles-Hong Kong |
238,825 (its two daily flights have now been extended to Bangkok and Ho Chi Minh City) |
|
68.5% |
San Francisco-Adelaide |
3,168 (new route: started in December 2025) |
|
69.0% |
Houston Intercontinental-Sydney |
53,226 |
|
69.1% |
Houston Intercontinental-London Heathrow |
273,837 |
|
69.6% |
Washington Dulles-Amsterdam |
100,665 |
|
70.3% |
San Francisco-Amsterdam |
80,405 |
|
* According to the DOT. MIninum of 2,500 roundtrip passengers |
** According to the DOT. Note the distance requirement, as stated above the table |
*** According to the DOT |
Most Of United’s Entries Were Transatlantic
Notice that six of the ten entries involved transatlantic markets. While not a like-for-like comparison, nine of Delta’s bottom-ten results were across the North Atlantic.
Let’s consider Washington Dulles to Dakar, which marked United’s introduction into Senegal. According to Cirium Diio data, the route began last spring but ended after less than a year. Despite only a three weekly service on the 203-seat Boeing 767-300ER, it was not expected to last long, for multiple reasons.
Dulles has a history with Dakar flights. South African Airways operated Johannesburg-Dakar-Dulles between 2006 and 2019, while Air Senegal had planned to fly to Dulles via JFK, before switching to Baltimore at the last minute. Neither airline now serves the US.
United coexisted with Delta in serving Dakar, with its flights being from New York JFK. And in 2026, Air Transat will lift off from Montreal to Dakar. These two carriers benefit from targeting Dakar’s top two North American markets. Unsurprisingly, booking data shows they were United’s most popular connecting destinations. Following the postponement of Air Transat’s Toronto-Accra route, questions remain about whether it’ll begin its first service to Senegal.
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Los Angeles To Heathrow?!
When all airlines are considered, Los Angeles-Heathrow is, of course, a massive market. It had nearly 1.5 million passengers last year. This included everyone who flew nonstop, regardless of their origin or destination.
Given how well-trafficked it is, you’d perhaps think that United’s load factor was an error. But the US DOT shows it filled just 63.8% of available seats, although this does not indicate how full its premium cabins were. In contrast, it was 78.6% for all nonstop airlines combined. It was United’s lowest result on the route in 30+ years. Half of the months had loads of less than 50.0%, including February 2025 (41.5%).
With under 120,000 passengers in 2025, it was its fourth-lowest traffic volume on record. Compared to 2024, when a double daily service existed for half of the year, only a daily operation was available. As traffic fell marginally more than capacity in 2025, the load fell slightly. In 2026, United continues to serve the route daily, primarily on the 257-seat 787-9. Will any changes materialize?







