169 Routes: A Look At United Airlines’ Houston Intercontinental Hub Flights

If all airlines are included, Houston Intercontinental is the USA's ninth-busiest airport by flights in the first half of 2024 (February-June). When the US Big Three are considered, it is the country's sixth-busiest airline hub. It ranks after America at Dallas Fort Worth, Delta at Atlanta (yes, second by flights), American at Charlotte, United at Chicago O'Hare, and United at Denver.