Chicago’s O’Hare and Atlanta’s Hartsfield-Jackson both claim to be the busiest airport in America.

Here’s the reality.

When it comes to total passengers, Atlanta wins.

In 2025, more than 106 million people passed through Atlanta, making it not just the busiest airport in the country, but the busiest airport on the planet.

Chicago O’Hare comes in second at nearly 85 million passengers.

Here’s where it gets interesting.

O’Hare actually beats Atlanta in the sheer number of daily flights, making it the busiest airfield in the country for aircraft operations.

For both airports, it’s not just about passenger numbers—it’s about distance.

Atlanta has seven concourses connected by an underground train.

O’Hare has four terminals, so be prepared to get your steps in.

Allow at least 90 minutes for you — and your luggage — to make your connecting flight, assuming your incoming flight is on time.