The flight between South Korea’s island of Jeju and the capital city of Seoul has once again ranked among the busiest air routes in the world, underscoring the continued dominance of short-haul, high-frequency travel across the Asia-Pacific region.
According to data from OAG, the 450-kilometre route offered 14.4 million passenger seats in 2025, a year-on-year increase of 1 percent. On an average day, airlines collectively provide close to 39,000 seats between the two destinations, making the corridor one of the most intensively served air links globally.
Seven airlines currently compete on the route, reflecting both its commercial importance and the unique geography of South Korea, where Jeju Island serves as the country’s primary leisure destination, remaining largely dependent on air travel. Despite reclaiming its position at the top of the global rankings, the Jeju–Seoul route is still operating at volumes 17 percent below pre-pandemic levels, highlighting how recovery in aviation remains uneven even on the strongest domestic markets.
The Jeju–Seoul connection links Jeju Island with the Seoul metropolitan area, primarily via Gimpo Airport, and has long been considered a barometer for domestic air demand in East Asia. High flight frequency, short travel time, and sustained leisure and business demand have historically kept the route among the world’s busiest, often rivaling or surpassing major trunk routes in larger countries.
Japanese domestic flights secured the second and third positions in OAG’s 2025 ranking. Services between Sapporo and Tokyo took second place, followed closely by flights linking Fukuoka and Tokyo. Both routes reflect Japan’s heavy reliance on air travel to connect distant regions with the capital, despite the country’s extensive high-speed rail network.
The Asia-Pacific region accounted for nine of the ten busiest air routes worldwide, reinforcing its role as the engine of global short-haul aviation. The only route outside the region to break into the top ten was the domestic Saudi Arabian flight between Jeddah and Riyadh, which ranked fifth overall. Notably, OAG identified this route as the fastest-growing among the top ten, driven by strong domestic travel demand and the kingdom’s broader economic and tourism expansion.
Australia also featured prominently, with the heavily trafficked route between Melbourne and Sydney ranking sixth. Often described as one of the world’s most competitive airline markets, the Melbourne–Sydney corridor continues to demonstrate the resilience of business travel alongside a steady rebound in leisure demand.
Beyond domestic routes, OAG’s analysis of international services revealed similarly concentrated patterns of demand. The most heavily served international route in 2025 was between Hong Kong and Taipei, with 6.8 million seats offered over the year. Other leading international routes included Cairo–Jeddah and Kuala Lumpur–Singapore, both reflecting strong regional, religious, and economic travel flows.
OAG analysts note that the concentration of the world’s busiest routes within Asia-Pacific highlights structural differences in how regions travel. Dense populations, limited land connections between key cities, and strong domestic tourism markets continue to favour high-frequency air services, even as sustainability concerns and alternative transport modes gain attention elsewhere.
The full list of the world’s busiest air routes in 2025 by total seat capacity, according to OAG, is as follows:
Jeju – Seoul, South Korea (14,384,766)
Sapporo – Tokyo, Japan (12,099,499)
Fukuoka – Tokyo, Japan (11,496,706)
Hanoi – Ho Chi Minh City, Vietnam (11,078,775)
Jeddah – Riyadh, Saudi Arabia (9,819,558)
Melbourne – Sydney, Australia (8,951,497)
Tokyo – Okinawa, Japan (8,052,864)
Mumbai – Delhi, India (7,642,016)
Beijing – Shanghai, China (7,454,950)
Shanghai – Shenzhen, China (7,138,673)
As global aviation continues its post-pandemic recovery, these rankings illustrate where demand has returned most strongly. For airlines and airports alike, the message is clear: short-haul, high-density routes in Asia-Pacific remain the backbone of global air travel in 2025.
