[10] The airport is American Airlines' third-largest hub and serves as its primary gateway to Latin America and the Caribbean.

Miami also serves as a focus city for Avianca, Frontier Airlines, and LATAM, both for passengers and cargo operations.

In June of 1928 Pan American Airways acquired 116 acres of land on NW 36th Street for the purpose of building a privately owned and operated international airport in Miami, Florida.

The establishment of a commercial airport and of regularly scheduled international passenger airline service by Pan Am was a transformative event for the City of Miami.

By September of 1928, Pan Am had begun to operate regularly scheduled Air Mail service between Miami and Havana.

Three hangars, two on the east and one on the west, provided housing and maintenance facilities for Pan Am's fleet of Sikorsky amphibian and Fokker aircraft.

During the first few years of its operation, from late 1928 until late 1930, it was from this busy airport that Pan American Airways historically pioneered U.S. international passenger aviation, inaugurating regularly scheduled Air Mail and passenger airline service from the U.S. to the West Indies, Caribbean, and Central and South America.

In 1940, Intercontinent Corporation, owned by William Pawley, built an aircraft manufacturing plant on land acquired immediately east of Pan American Field.

Miami Army Airfield opened in 1943 on 1400 acres of land acquired during World War II to the south of Pan American Field.

[12] Following World War II, the Dade County Port Authority embarked on a long-planned airport expansion in order to meet Miami's increasing commercial aviation needs.

Pan American's former NW 36th Street terminal building continued to serve as the hub for the new Miami International Airport.

The former domed-roofed Pan Am terminal building was extensively remodeled and enlarged, the words “Miami International Airport” now curving across its façade.

In the late 1940s, Pan Am and Eastern also expanded their bases at MIA on NW 36th Street, which made the airport the world's largest commercial aircraft maintenance and overhaul facility at the time.

Scheduled airlines had outstripped ships, trains and buses to become the state’s as well as the nation’s largest carriers of interstate and international traffic.

Delta had joined Pan Am, Eastern and National to become MIA's "Big Four" carriers and the airport also served a host of smaller scheduled and non-scheduled airlines.

In the late 1970s and early 1980s, Air Florida had a hub at MIA, with a nonstop flight to London, England which it acquired from National upon the latter's merger with Pan Am.

[16] British Airways flew a Concorde SST (supersonic transport) triweekly between Miami and London via Dulles International Airport in Washington, D.C., from 1984 to 1991.

[16] Later in the 1990s, American transferred more employees and equipment to MIA from its failed domestic hubs at Nashville, Tennessee, and Raleigh–Durham, North Carolina.

[23] Today Miami is American's largest air freight hub and is the main connecting point in the airline's north–south international route network.

[28] The terminal was ultimately completed in 2011 and included Skytrain, an automated people mover system, as well as a wing for American Eagle commuter flights.

Its remaining international routes from Miami to Europe and Latin America were sold to United Airlines for $135 million as part of Pan Am's emergency liquidation that December.

[30] Iberia also established a Miami hub in 1992, positioning a fleet of DC-9 aircraft at MIA to serve destinations in Central America and the Caribbean.

[35] To meet such a demand, the Miami-Dade Board of County Commissioners approved a $5 billion improvement plan to take place over 15 years and concluding in 2035.

Miami-Dade Transit operates an Airport Flyer bus that connects MIA directly to South Beach.

The largest privately owned facility is the Centurion Cargo complex in the northeast corner of the airport, with over 51,000 m2 (550,000 sq ft) of warehouse space.