The airline route connecting John F. Kennedy International Airport (JFK) and Los Angeles International Airport (LAX) ranked as the busiest domestic route in the United States, according to data released this week from OAG, a leading the leading data platform for the global travel industry. London Heathrow (JFK-LHR) retained its international lead despite slight capacity softening, the data showed.
The rankings are based on OAG’s global airline schedules data. OAG noted that there is continued strength across major domestic corridors, and that international services trail high-volume domestic markets.
On domestic routes, the JFK-LAX route expanded in 2025, with 3.43 million seats, up 9% year-over-year, reinforcing its status as the leading U.S. transcontinental market. New York LaGuardia – Chicago O’Hare (LGA–ORD) followed in second place, growing 7% to 3.33 million seats, while Los Angeles – San Francisco (LAX–SFO) ranked third, increasing 5% to 3.31 million seats.
Several leisure-focused routes saw capacity declines compared with 2024, including Atlanta – Orlando (ATL–MCO) (-7%) and Honolulu – Kahului (HNL–OGG) (-10%). Meanwhile, Los Angeles – Chicago O’Hare (LAX–ORD) posted moderate growth of 4%, underscoring the resilience of large hub-to-hub markets.
New York JFK – London Heathrow (JFK–LHR) remained the USA’s busiest international route with 3.97 million seats in 2025, down slightly (-1%) from 2024. It would top the list in a combined ranking of international and domestic routes, however the second busiest international route, Orlando (MCO) – San Juan (SJU) would not figure in a combined top ten with its 2.23M seats placing it behind many more domestic routes.
“The busiest routes highlight a strong US market in 2025, with fierce competition between both legacy and low-cost carriers,” said John Grant, chief analyst at OAG. “With key airport pairs seeing higher than average rates of growth there remains an appetite from both airlines and travelers on these key routes and more capacity returned to the market through the year. London Heathrow – New York JFK remains the busiest single route with airlines consistently adding new products in the premium cabins as they seek to attract higher yielding customers.”
