World's busiest flight routes 2021: Sydney-Melbourne route back among world's busiest

A surge in flights between Sydney and Melbourne has seen the route climb back into the world's 10 busiest, data shows.

Flight data analyst OAG ranks the world's busiest routes by the number of seats available. In April, Sydney-Melbourne climbed to number seven on the top 10 list, with 598,779 seats.

As Australia's airlines reduced domestic capacity in the wake of the COVID-19 outbreak and state border closures last year, the Sydney-Melbourne route disappeared from the top 10.

Previously it was the second-busiest route in the world, behind only South Korea's domestic route between Seoul and Jeju island. The latter route remains the world's busiest now, with more than 1.4 million seats for April.

Travel has bounced back in Australia, with Virgin Australia announcing last month plans to lease eight or nine more Boeing 737s in order to increase capacity on domestic routes.

Qantas chief executive Alan Joyce told  the CAPA Centre for Aviation this month the airline had seen Australia's domestic market get stronger each quarter and he expected Qantas to be back to 80 per cent of its pre-COVID-19 capacity in the fourth quarter of this financial year.

"Despite the stop and start, people are getting comfortable with what the situation is around borders," he said. "They're travelling. And then each time it looks like when the borders are closed, it's for a shorter period, the rebound is faster."

The Sydney-Melbourne route now has a fourth player in addition to Qantas, Virgin and Jetstar, with regional airline Rex making its first foray into connecting capitals, launching on the route in February.

While the federal government's tourism scheme for half-price flights has also reportedly boosted airfare sales recently, the scheme will not have impacted the Sydney-Melbourne route as it was restricted to selected regional destinations from the capitals.


Besides Sydney-Melbourne, all other routes on the top 10 list were in Asia, with Hanoi-Ho Chi Minh in Vietnam, Beijing-Shanghai in China, Fukuoka-Tokyo in Japan and Guangzhou-Shanghai in China rounding out the top five.

South Korea has long held the busiest route in the world and while capacity was reduced on the Seoul-Jeju route during COVID-19, it has maintained its place at the top of the list. Jeju is considered the Hawaii of Korea and is a UNESCO World Heritage site. Along with beaches, it's also renowned for its volcanic lava tubes and for Mount Halla - the highest mountain in Korea.

The world's busiest international route for April was Orlando, US, to San Juan, Puerto Rico, which OAG categorised as international despite Puerto Rico being an unincorporated territory of the US. The second busiest route was Moscow to Domodedovo-Simferopol in Crimea - again classified as an international flight despite the region being annexed by Russia, but internationally still considered part of Ukraine. Delhi-Dubai was third and the busiest international route between two completely separate countries.

With the advent of the world's first major travel bubble between Australia and New Zealand on April 18, we may see Sydney-Auckland or Melbourne-Auckland climb into the top 10 international routes next month.

The world's busiest flight routes in April 2021 (by number of seats)

  1. Jeju International-Seoul Gimpo 1,472,498
  2. Hanoi-Ho Chi Minh City 932,454
  3. Beijing-Shanghai Hongqiao 754,778
  4. Fukuoka-Tokyo Haneda 648,746
  5. Guangzhou-Shanghai Hongqiao 634,916
  6. Sapporo New Chitose-Tokyo Haneda 633,656
  7. Melbourne-Sydney 598,778
  8. Shanghai Hongqiao-Shenzhen 582,534
  9. Jeddah-Riyadh 545,628
  10. Seoul Gimpo-Busan 514,606

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