In this post we’re going to look at the busiest air routes in the world, or at least what they were before the pandemic disrupted domestic and international travel. We’ll look at the busiest domestic and international connections by annual passenger numbers, as well as the busiest air routes in every continent.
The figures come from this post which is based on data from Sabre. They relate to 2018 air passenger numbers and are rounded up or down to the nearest 100,000. Clearly almost all of these routes would have been significantly less busy in 2020 and 2021.
The busiest air routes in the world – by annual passenger numbers
The Top 5 – All Domestic Routes
- Jeju to Seoul-Gimpo – 14.1 million
The world’s busiest air route is in South Korea with over 14 million people flying from Seoul-Gimpo to Jeju each year. There are staggeringly over 100 flights per day between the Korean capital and the island province of Jeju with eight different carriers competing. Despite there only being around 600,000 permanent residents on Jeju, many are dependent on the air connections to get to/from the mainland and it’s also a popular tourist destination for Koreans which accounts for much of its air traffic.
- Sapporo to Tokyo-Haneda – 9.7 million
Japan is a country famous for its outstanding rail network but it’s a long old trek out to its northernmost island of Hokkaido. The fastest links between the island’s largest city Sapporo and Japanese capital are by air with the Sapporo-Tokyo Haneda route serving nearly 10 million passengers each year.
- Sydney to Melbourne – 9.2 million
The busiest air route outside of Asia is in Australia and predictably it’s the connection between Melbourne and Sydney. The two largest Australian cities are around 700 km apart and without fast rail connections, the most common way to get between the two cities is to fly. Both only have one major airport which also pushes it higher up these rankings as some of the busiest city links in the world utilise more than one airport in each destination.
- Fukuoka to Tokyo-Haneda – 8.8 million
Back to Japan for number four and back to Tokyo-Haneda, one of the world’s busiest airports. Just under nine million people flew between the airport and Fukuoka in 2018. Located on the island of Kyushu, Fukuoka is slightly better connected to the other major Japanese cities than Sapporo, but many still opt to fly to Tokyo with around 900 km between the two.
- Mumbai to Delhi – 7.4 million
At number five, Mumbai to Delhi is the busiest air route in India. As the country continues to develop and more people rise into the middle class, this could potentially grow to become the world’s busiest in the coming decades unless alternative airports are built. Like Japan, Indians also largely rely on rail for their travel needs but the rise of budget airlines over the past decade has made it much more affordable to travel between Mumbai and Delhi, which is also the longest route by flying time in the top five, taking around two hours.
The Busiest International Air Routes
- Taipei to Hong Kong-Taoyuan – 6.5 million
The busiest international air route in the world is Taipei to Hong Kong-Taoyuan with around 6.5 million people making the trip in 2018, only marginally less than the entire population of Hong Kong. Both places clearly have strong links to China but it’s certainly an international route. The flying time is under two hours and with Taiwan being an island nation, it’s just about the only realistic way to get to/from the two places.
- Jakarta to Singapore – 4.8 million
Over to Southeast Asia next and to Singapore, another major global hub for air travel and what is largely viewed as the world’s best airport. Indonesia is visible from the shores of Singapore but the capital Jakarta is too far away to get to quickly via land or sea. The two countries retain strong ties and while only the 19th busiest air route overall, Jakarta to Singapore is the second busiest international route.
- Kuala Lumpur to Singapore – 4.5 million
Singapore’s primary air link to its northern neighbour Malaysia is next. While many opt for rail/road links to complete what is only a 300 km journey, bargain flights and two excellent airports with fast links to their respective cities make flying an attractive option too. Although international, this is actually the second shortest of the world’s 30 most popular air routes, with only Bogota-Medellin in Colombia a fraction quicker.
- Hong Kong to Shanghai-Pudong – 4.1 million
With China increasingly exerting its authority over Hong Kong, this one will stir some debate as to whether it should really be classed as an international air route or not. Hong Kong and Shanghai are two of Asia and indeed the world’s major business cities so it’s understandable that there are lots of air links and that’s only likely to continue as China’s economic growth continues. There are other options for people travelling from Shanghai to the Hong Kong/South China region with the Shanghai-Shenzhen and Shanghai-Guangzhou routes even busier, although those flights depart from Hongqiao Airport as opposed to Pudong which mostly handles international services.
- Hong Kong to Bangkok-Suvarnabhumi – 3.5 million
Bangkok-Suvarnabhumi is another of Asia’s busiest international airports. Its busiest air link is with the popular Thai beach island of Phuket but the connection to Hong Kong isn’t far behind with around 3.5 million passengers in 2018. The flight distance is 1694 km, making it the 6th longest of the world’s 50 busiest air routes. New York-JFK to Los Angeles is comfortably the longest at 3982 km but it only ranks as the 29th busiest route globally.
The busiest air routes in every continent
As you may have noticed, Asia features prominently in this post with almost all of the world’s busiest international and domestic air routes. Outside of Asia and Oceania, there are no routes serving more than 5 million passengers each year as of 2018, and that’s unlikely to change soon given the disruption to air travel we have witnessed of late due to the covid-19 pandemic.
| Busiest Air Route | Passengers (2018) | |
| Asia | Jeju to Seoul-Gimpo | 14.1 million |
| Oceania | Sydney to Melbourne | 9.2 million |
| Europe | Madrid Barajas to Barcelona El Prat | 2.5 million |
| Africa | Cape Town to Johannesburg | 4.5 million |
| South America | São Paulo–Congonhas to Rio de Janeiro-Santos Dumont | 4.2 million |
| North America | Cancun to Mexico City | 4.9 million |
The busiest air route just in Europe is Madrid to Barcelona, however numbers have fallen significantly since the construction of a high-speed rail link. There are also actually more people who fly between London Heathrow and New York JFK each year than those who use Europe’s busiest route in Spain.
It’s also worth noting that some cities have several airports. Purely in terms of city connections, the London-Dublin route is Europe’s busiest with an estimated 5 million travellers each year during normal times. London Heathrow, one of the busiest airports in Europe, also features prominently in the list of busiest long haul flight routes with its connections with Dubai, Singapore, Los Angeles and Hong Kong, as well as New York, featuring lots of flights each week.
São Paulo to Rio is South America’s busiest air route both in terms of travel between the two cities and specific airports. Cape Town to Johannesburg stands alone as the busiest in Africa and despite having some of the busiest airspace in the world, the United States does not feature with Mexico City-Cancun topping the rankings in North America.
This article was published in June 2021. Passenger number data relates to the 2018 calendar year.
Featured Image of Asiana Airlines flight via InSapphoWeTrust, CC BY-SA 2.0