A new report from aviation data analysts Official Aviation Guide (OAG) reveals the latest review of the world’s busiest flight routes and trends in 2025, scrutinising capacity and, for the first time, airfares on the top routes.
1. Jeju to Seoul
Nine of the top ten busiest routes for the year were in the Asia Pacific region, with the busiest of all in South Korea, between Jeju (CJU) and Seoul Gimpo (GMP). This route of only 450 km (243 nautical miles) saw 14.4 million scheduled seats in 2025, or nearly 39,000 daily seats. Capacity rose 1% and airfares dropped 11% year-on-year, on what OAG calls a “very competitive route.”
| Route Ranking 2025 | Scheduled Seats 2025 |
| Jeju International – Seoul GImpo | 14,384,766 |
| Sapporo New Chitose – Tokyo Hanaeda | 12,099,499 |
| Fukoka – Tokyo Hanaeda | 11,496,706 |
| Hanoi – Ho Chi Minh City | 11,078,775 |
| Jeddah – Riyadh | 9,819,558 |
| Melbourne – Sydney | 8,951,497 |
| Tokyo Hanaeda – Okinawa Naha | 8,052,864 |
| Mumbai – Delhi | 7,642,016 |
| Beijing – Shanghai Hongqiao | 7,454,950 |
| Shanghai Hongqiao – Shenzhen | 7,138,673 |
2. Sapporo New Chitose to Tokyo Haneda
Sapporo New Chitose (CTS) to Tokyo Haneda (HND) took second place with a “staggering” 12.1 million seats in 2025It’s another 1% year-on-year increase but represents “near-full recovery” from COVID-19, OAG reports.
3. Fukuoka to Tokyo Haneda
It’s another Japanese route to the capital in third place, and another 1% growth. With 11.5 million seats scheduled in 2025, it has also recovered to just beyond pre-pandemic levels.
4. Hanoi to Ho Chi Minh City
Vietnam’s largest domestic route between Hanoi (HAN) and Ho Chi Minh City (SGN) is also the world’s fourth busiest. One million seats were scheduled in 2025, a 4% increase in year-on-year and 8% above 2019 levels, OAG notes. The analysts also point out how competitive it is, with six carriers operating in 2025 and a drop of 11% for airfares, taking them to an average of just $67 (€57).
5. Jeddah to Riyadh
In fifth place is the fastest growing route in the top ten from Jeddah (JED) to Riyadh (RUH), up three places year-on-year. OAG highlights that this is “Saudi Arabia’s flagship domestic route between the two largest cities in the Kingdom.” Scheduled seat numbers grew 13% in 2025, reaching 9.8 million, in line with “overall domestic growth,” but with just three airlines operating it, average economy airfares on the route rose 27% year-on-year to hit $95 (€81) one way. It is the only route in the top ten outside Asia.
Regional analysis
Elsewhere in world regions, the analysis shows South Africa’s Cape Town – Johannesburg (5,475,986 seats) topped the African list, Colombia’s Bogata – Medellin (6,219,202 seats) topped Latin America; Canada’s Vancouver – Toronto was the busiest in North America, and in Europe, Spain’s meteoric tourism market has kept Barcelona – Palma (2,955,696 seats) in first place year-on-year.
