Heathrow Lost the World’s Busiest Title to a Rule Written in 2001

_{Heathrow flew 477,883 air transport movements last year against a legal ceiling of 480,000, and Incheon took the world’s busiest international title by 600,000 passengers.}

Airports Council International’s preliminary first-half data, drawn from 1,234 airports, puts Incheon International at 38.39 million international passengers for January through June 2026. London Heathrow came second at 37.79 million. Singapore Changi took third with 34.53 million. Incheon International Airport Corporation announced the result on August 13, and the coverage that followed read it as an arrival: three decades of Korean aviation policy paying off, a Western hub displaced by an Asian one.

The gap is 600,000 passengers. Call it 1.6 percent, or about five days of Heathrow traffic.

IIAC has an explanation ready. The airport credits the Middle East. Travelers who once connected through Dubai on their way to Europe rerouted east while UAE airspace was constrained, and Incheon’s Europe-bound transfer traffic rose 63.2 percent year on year. That number is real and the airport is entitled to it. It is also 214,000 passengers in total, which cannot move a ranking by 600,000.