The 10 biggest airline hubs in the US

For years, Hartsfield-Jackson Atlanta International Airport (ATL) has held the title of the world's busiest airport.A big reason for its dominance: the massive Delta Air Lines operates from there.It's why frequent Delta flyers know all too well, a Delta flight often involves a connection in Atlanta.But each of the nation's "Big Three" legacy airlines have a hub-and-spoke setup that filters millions of flyers through a handful of really big airports.Flying American Airlines? You'll often find yourself in Dallas or Charlotte. If you're a regular United Airlines customer, there's a good chance you're a regular at Chicago's O'Hare International Airport (ORD).So what are the biggest airline hubs in the U.S.?Let's run down the top 10.The biggest airline hubs in the US by departuresHere's how the biggest airline hubs in the U.S. stacked up in 2025 when it came to the total number of departing flights last year, per data from aviation analytics firm Cirium.Not surprisingly, Delta's presence in Atlanta held the top spot.Reward your inbox with the TPG Daily newsletterJoin over 700,000 readers for breaking news, in-depth guides and exclusive deals from TPG’s expertsBy signing up, you will rec...