The Civil Aeronautics Board (CAB) was an agency of the federal government of the United States, formed in 1938 and abolished in 1985, that regulated aviation services and conducted air accident investigations. The agency was headquartered in Washington, D.C.

The United States has an extensive air transportation network. In 2013, there were 86 airports in the U.S. that annually handled over 1,000,000 passengers each. The civil airline industry is entirely privately owned and has been largely deregulated since 1978, while most major airports are publicly owned. The three largest airlines in the world by passengers carried are U.S.-based; American Airlines is number one after its 2013 acquisition by US Airways. Of the world's 50 busiest passenger airports, 16 are in the United States, including the top five and the busiest, Hartsfield–Jackson Atlanta International Airport. In terms of cargo, in 2015, eight of the world's thirty busiest airports were in the U.S., including the world's second-busiest, Memphis International Airport, just behind Hong Kong International Airport in Hong Kong. Private aircraft are also used for medical emergencies, government agencies, large businesses, and individuals.