The three-letter IATA code for Hartsfield-Jackson Atlanta International Airport is ATL. Located 10 miles south of Downtown Atlanta, it consistently ranks as one of the world's busiest airports by passenger traffic. The code "ATL" is used globally on luggage tags, boarding passes, and flight tracking software to identify this massive hub, which serves as the primary base for Delta Air Lines. In 2026, the airport continues to utilize its efficient "Plane Train" to move passengers between its seven concourses (T, A, B, C, D, E, and F). If you are looking for the four-letter ICAO code used by pilots and air traffic controllers, it is KATL. The airport's identity is so tied to the code that "The ATL" has become a common nickname for the city itself in popular culture.