World's busiest airline flight routes 2021: Orlando, US - San Juan, Puerto Rico named world's busiest route

With the constantly changing effect of the coronavirus pandemic on the travel industry, there is little that can be regarded as "normal". A case in point is the top 10 busiest international air routes.

Last month, Dubai to London Heathrow took out the top spot, but new travel restrictions from the UK government after a flare-up of Covid-19 in the UAE mean it has plummeted out of the top 10.

Instead, it has been replaced at the top by Orlando, US to San Juan, Puerto Rico. The route from Florida to the American territory sold more than 135,000 seats, according to business and aviation analytics firm OAG.

The near three-hour flight is defined as international even though US citizens do not need a passport for entry.

Walt Disney World Resort, other Orlando attractions, and hotels are trying to attract locals for spring break with never-before-seen deals.

In second place is Delhi, India to Dubai (129,683 seats), followed by Cairo, Egypt to Jeddah in Saudi Arabia (128,665), Paris, France to the Caribbean island of Guadeloupe (118,594) and Tehran, Iran to Turkey's Istanbul (110,936).

The top 10 busiest domestic routes were pretty much all based in Asia, with Jeju-Seoul (South Korea –1,199,037 seats), Hanoi-Ho Chi Min (Vietnam – 1,085,472) and Sapporo-Tokyo (Japan – 589,285) taking out the top three spots.

As a comparison, in 2019 before the pandemic, the route between tourist hot spot Jeju and Seoul Gimpo airport had more than 17 million annual seats, equivalent to around 48,000 on average each day.

For global routes, Hong Kong-Taipei had the greatest number of seats - 7,965,538. It was followed by two Singapore routes - Kuala Lumpur in Malaysia (5,560,894), and the Indonesian capital Jakarta (5,480,000).

See also: How many of the world's air routes have vanished since COVID-19 hit