Spokane International Airport (GEG) traces its origins to a World War II military installation known as Geiger Field, established by the U.S. Army Air Corps in 1941 and named for Major Harold Geiger, an aviation pioneer killed in a crash in 1927. Geiger Field served as a training base for B-17 Flying Fortress heavy bombardment units and as an aircraft maintenance depot for the Air Technical Service Command. When the war ended, the facility was transferred to Spokane County and developed into a commercial airport. United and Northwest Airlines began operations there on July 22, 1946. The airport retained the GEG code, a direct echo of its military identity, long after it was renamed Spokane International Airport in 1960.

Situated roughly 7 miles west-southwest of downtown Spokane, GEG is the primary air gateway for the Inland Northwest, a catchment area spanning approximately 30 counties across eastern Washington, northern Idaho, and western Montana. It is the second busiest airport in Washington state by passenger volume, handling over 4.3 million passengers in 2025. The airport has 2 runways and a single terminal divided into 3 concourses: A, B, and C. The Concourse A and B complex, designed by architects Warren C. Heylman and William Trogdon, opened in 1965. Concourse C has been expanded under the Terminal Renovation and Expansion (TREX) program, with the first 3 new gates opening in June 2024.

Carriers including Alaska Airlines, Delta Air Lines, American Airlines, Southwest Airlines, and United Airlines serve the airport, with top nonstop routes running to Seattle, Denver, Portland, Salt Lake City, and Phoenix. GEG is classified by the FAA as a small-hub primary commercial service airport and supports exclusively domestic routes. The airport is jointly owned by the City of Spokane and Spokane County and is self-sustaining through fees, leases, and concessions.