Salt Lake City International Airport (IATA: SLC, ICAO: KSLC, FAA LID: SLC) is a joint civil-military international airport located about 4 mi (6.4 km; 3.5 nmi) west of Downtown Salt Lake City, Utah, United States. The airport, along with the much smaller Provo Airport (PVU) and Ogden–Hinckley Airport (OGD) are the closest commercial airports for more than 3 million people and is within a 30-minute drive of nearly 1.3 million jobs. The airport serves as a hub for Delta Air Lines and is a major gateway to the Intermountain West and West Coast. The airport sees 343 scheduled nonstop airline departures per day to 93 cities in North America, Asia, and Europe. It is by far the busiest airport in Utah.

Salt Lake City International Airport continues to rank high for on-time departures/arrivals and the fewest flight cancellations among major US airports. The airport ranked first for on-time departures and arrivals and first for the percentage of cancellations as of April 2017. The airport is owned by the City of Salt Lake City and is administered by the municipal Department of Airports.

In 2024, the airport set an all-time record with 28,364,610 passengers served, a 5.2% increase from 2023.

In 1911, a site for an air field was chosen on Basque Flats, named for Spanish-French sheep herders who worked the fields in the then-desolate area of the Salt Lake Valley, where a cinder-covered landing was subsequently created. The Great International Aviation Carnival was held the same year and brought aviation pioneers representing Curtiss Aeroplane and Motor Company and a team representing the Wright Brothers to Salt Lake City. World-famous aviator Glenn H. Curtiss brought his newly invented Seaplane to the carnival, a type of airplane that had never been demonstrated to the public. Curtiss took off from the nearby Great Salt Lake, awing the 20,000 spectators and making international headlines.

For several years, the new field was used mainly for training and aerobatic flights. That would change in 1920 when the United States Postal Service (USPS) began air mail service to Salt Lake City. The city bought a 100-acre tract around Basque Flats for $4,000 and built a field, hangar and other facilities. In the same year, the airfield was given the name Woodward Field, named for John P. Woodward, a local aviator. The first transcontinental air mail flight landed at Woodward Field on September 8.

In 1925, the postal service began awarding contracts to private companies. Western Air Express, the first private company to carry U.S. mail, began flying from Salt Lake City to Los Angeles via Las Vegas. Less than a year later, Western Air Express would begin flying passengers along the same route. Western Air Express later became Western Airlines, which had a large hub in Salt Lake City.

Charles Lindbergh visited Woodward Field in 1927, drawing many spectators to see The Spirit of St. Louis. During the next few years the airport would gain another runway and would span over 400 acres (1.6 km²). In 1930 the airport was renamed Salt Lake City Municipal Airport.

The first terminal and airport administration building was built in 1933 at a cost of $52,000. By then, United Airlines had begun serving Salt Lake City on flights between New York City and San Francisco.