Who Knew!? In 2014, Atlanta and Chicago rivaled each other to claim the busiest airport in the world. As with all statistics, it depends on which numbers you are comparing. Atlanta’s Hartsfield-Jackson, was considered the busiest airport in the world handling themost passengers (96 million) vs. Chicago’s O’Hare (66.7 million). O’Hare though did rank #1 in the number of flights: Chicago 881,933 vs. Atlanta 868,359. In comparison, Toronto Pearson International Airport, Canada’s largest aviation hub, managed 38.5 million passengers and 432,827 flights in 2014. Click here to see the world rankings.