OAG: USA’s and the World’s Busiest Airline Routes in 2025

New York JFK – Los Angeles (JFK–LAX) ranks as the busiest domestic route and internal routes continue to dominate the USA’s busiest rankings in 2025.
New York JFK – London Heathrow (JFK-LHR) retains its international lead despite slight capacity softening; other international services trail high-volume domestic markets.

OAG, the leading data platform for the global travel industry, today released analysis of the Busiest Airline Routes in the USA in 2025, highlighting continued strength across major domestic corridors. The rankings are based on OAG’s Global Airline Schedules Data.

Domestic services continue to account for most of the busiest airline routes in the USA. New York JFK – Los Angeles (JFK–LAX) ranks as the busiest domestic route 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) follows in second place, growing 7% to 3.33 million seats, while Los Angeles – San Francisco (LAX–SFO) ranks 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) remains 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.

Also from OAG:

Nine of the Top Ten Busiest Routes operate in the Asia Pacific region.

The busiest airline route of 2025 is Jeju (CJU) to Seoul Gimpo (GMP):

This route has 14.4 million scheduled seats in 2025, this is equivalent to almost 39,000 daily seats operating on this short sector of just 243 nautical miles.
Capacity on the route is 1% above 2024 levels, but remains 17% behind 2019 levels.
Seven carriers operate on this very competitive route.
Airfares have dropped by 11% year-on year to $44 one-way.

The second and third placed busiest routes are both in Japan – which continues to maintain a strong position despite an extensive high speed rail network covering the country:

Sapporo New Chitose (CTS) to Tokyo Haneda (HND) is in second place with a staggering 12.1 million seats in 2025; up 1% year-on-year and only 3% below pre-pandemic volumes, indicating near-full recovery.
Fukuoka (FUK) to Tokyo Haneda (HND) is in third place growing by 1% vs 2024 with 11.5 million seats scheduled in 2025, this exceeds 2019 levels by 1%, making it one of the few major domestic routes to surpass pre-pandemic capacity.

Vietnam’s largest domestic route between Hanoi (HAN) and Ho Chi Minh City (SGN) is the fourth busiest route:

1 million seats were scheduled in 2025, a 4% increase in year-on-year and 8% above 2019 levels.
This route is highly competitive with six carriers operating in 2025.
Airfares on this route have decreased by 11% year-on-year with the average one-way ticket costing $67.

The fastest growing route in the top ten is fifth placed Jeddah (JED) to Riyadh (RUH):

Saudi Arabia’s flagship domestic route between the two largest cities in the Kingdom is the only route in the top ten outside of Asia Pacific.
The route has increased by 13% YoY with 9.8 million seats in 2025 – in line with overall domestic growth this year in Saudi Arabia – and is now 22% above 2019 levels.
Average economy airfares have also increased year-on-year by 27% to $95 one-way.
Three airlines operate on this 460 mile route.

The busiest domestic route in the USA in 2025 is New York JFK (JFK) to Los Angeles (LAX), with 3.4 million seats. Capacity has grown by 9% compared with 2024, although it remains 20% lower than 2019 levels.

New York La Guardia (LGA) to Chicago O’Hare (ORD) is in second place, with 3.3 million seats, 7% increase YoY. Despite this annual growth, the route is still 13% below 2019 levels.

Los Angeles (LAX) to San Francisco (SFO) ranks third with 3.3 million seats, up 5% YoY; however, the route remains 29% lower than 2019.

Further down the rankings, the Denver (DEN) to Phoenix (PHX) corridor stands out with 3.1 million seats, only 3% lower than last year but a substantial 23% above 2019. By contrast, Honolulu (HNL) to Kahului (OGG) – the busiest US domestic route in 2023 -has fallen to seventh place, operating 3.0 million seats in 2025, a 10% reduction YoY; however, it is still 6% above 2019.

KEY POINTS

The world’s busiest domestic route in December 2025 is South Korea’s Jeju International (CJU) to Seoul Gimpo (GMP), with 1.46 million seats. This represents a strong 33% increase in capacity compared to December 2024, making it the fastest-growing route in the Top 10.
Vietnam’s Hanoi (HAN) to Ho Chi Minh City (SGN) moves into second place with 1.07 million seats, up 25% year-on-year.
In third place is Japan’s Sapporo New Chitose (CTS) to Tokyo Haneda (HND) with 1.03 million seats, recording stable capacity versus last year.
Close behind, Fukuoka (FUK) to Tokyo Haneda (HND) ranks fourth with just over 1 million seats, a modest 2% increase vs last year.
Jeddah (JED) to Riyadh (RUH) is in fifth place, and Shanghai (SHA) to Shenzhen (SZX) is in ninth place. These routes also stand out as the fastest-growing major markets, with capacity increasing by 15% and 14% respectively compared to last year.