Over the last 10 years the number one and two airports by seat capacity – Atlanta and Beijing – have stayed constant, though both have grown in capacity. London Heathrow dropped from third biggest down to seventh. It doesn’t have the space to grow without a third runway.

A decade ago the list included Frankfurt, Madrid, and Dallas Fort-Wort but those have been outpaced over the last ten years.

British Airways Aircraft at London Heathrow

In the coming years Tokyo’s Haneda airport may become the world’s busiest by seat capacity – beating Atlanta – with new slots opening up in April. Meanwhile Beijing Capital airport is likely to shrink going forward as several airlines shift over to the farther-out Beijing Daxing.

Dubai airport which as far as I know has only international flights has the most international seat capacity of any airport. Interestingly Dubai’s Al Maktoum airport (Dubai World Central) used to have domestic service to Sir Bani Yas Airport on Rotana Jet between 2012 and 2017.

Dubai International Airport

Here’s the list, compiled by OAG of the 10 airports with greatest seat capacity in 2019.

Airport		Scheduled Seats
Atlanta		63,311,424
Beijing Capital		62,736,387
Tokyo Haneda		54,891,691
Dubai		53,984,063
Los Angeles		51,504,468
Chicago O’Hare		50,554,172
London Heathrow		50,180,465
Shanghai Pudong		46,937,025
Paris Charles de Gaulle		45,245,998
Hong Kong		45,199,309

Chicago O’Hare will look a lot busier if ranked by departures. There aren’t nearly as many small jets flying out of world airports like Beijing and Dubai as there are U.S. airports operating myriad domestic routes.