American Airlines Vs. Delta Vs. United: Which Carrier Has The Longest Nonstop Flights?

As everyone knows, American Airlines, Delta Air Lines, and United Airlines are the US’s Big Three operators. In November/December, Cirium Diio data shows they’ll collectively have 278 daily international long-haul departures. They’ve increased from 258 in those months in 2024. With 45% of the services, United is by far the leading carrier. Delta is second (31%), followed by American (24%).

Compared to last year, all three airlines have slightly more services. United stands out, with its offering up by 13% year-over-year. This might mean excessively high capacity, especially in November, which is among the worst months of the year for demand to Northern Hemisphere destinations. The potential consequences of this are obvious.

16h 15m+: Their Longest Nonstop Flights In November/December

The following list is based on the maximum block time, with at least 16h 15m required to be included. Block time is what is in booking engines, schedules, etc. This is measured as chocks-off-to-chocks-on. It includes taxi time at both airports, the actual flight, and a period for short delays. It balances productivity with slot possession (where relevant) and the need for as competitive a time as possible.

Only nonstop links are included. This rules out United’s return to Bangkok and Ho Chi Minh City on October 24 and 25, both of which will be served on a one-stop basis from Los Angeles via Hong Kong. At 16h 05m, the Los Angeles to Hong Kong leg was too short to be included.

United & Delta Have Longer Flights Than American

Given that United and Delta both have a larger long-haul presence than American, it is perhaps appropriate that the oneworld member’s longest nonstop service is shorter than its competitors. Of course, its longest link—16h 50m from Dallas to Brisbane—is still substantial and an ultra-long-haul service.

When all carriers are considered, Dallas is Brisbane’s longest market. However, it only ranks third from the Texas airport. It has a shorter block time than Melbourne and Sydney, both of which are served by fellow oneworld member and close partner Qantas.

American launched the very long route to Queensland’s capital in October 2024. Between then and May 2025, the US Department of Transportation indicates it filled 73% of the available seats. Given it was a brand-new market and is undoubtedly underpinned by financial incentives, this says little of its performance. However, it is trying to improve: it will have a sub-daily operation for more weeks in November/December than a year ago.

Hang On: Where Are Other Very Long Australian Services?

Multiple entries do not have a long enough maximum block time to be featured. They include various links to Australia, four of which have a maximum time of 15h 55m. They are Delta from Los Angeles to Melbourne (new route), United from Los Angeles to Melbourne, and United from San Francisco to Adelaide (new route) and Melbourne.

On December 3, Delta will lift off from Los Angeles, which is the world’s ninth-busiest airport for aircraft movements, to Melbourne. Served three times weekly on the high-premium, 275-seat A350-900, it will become Delta’s third Australian city after Sydney and Brisbane. It contributes to SkyTeam’s US-Australian development, which has increased from 9% to 11% in a year.

On December 11, United will begin the first-ever flight from the US to Adelaide, which is the South Australian capital. Service from its Pacific hub of San Francisco will run three times weekly on the 787-9. Significant financial incentives and other risk-sharing activities will underpin it. It is bound to make my celebratory Weekly Routes article (see the most recent edition).