Charlotte Douglas International Airport (CLT) operates with one primary terminal building that is subdivided into five distinct concourses: A, B, C, D, and E. While many travelers refer to these concourses as "terminals," they are all physically connected under a single roof, allowing passengers to walk between any gate without exiting security or using a shuttle bus. This "hub-and-spoke" layout is highly efficient for American Airlines, which uses CLT as its second-largest hub. The main terminal houses all check-in counters, security checkpoints, and baggage claim carousels. Concourse A primarily serves non-American Airlines carriers like Delta and United, while Concourses B and C are the main hubs for American's domestic mainline flights. Concourse D handles international arrivals and departures, and Concourse E is dedicated to regional jet operations (American Eagle). In 2026, the airport is nearing the completion of its "Destination CLT" expansion project, which has significantly increased the square footage of the main terminal lobby to handle the more than 50 million annual passengers that pass through the facility.