Lethbridge has played a significant role in Western Canadian aviation history. In the early part of the 20th century, a number of ad-hoc sites were used to accommodate emerging aviation activities in the region. The Exhibition Grounds and later, the site of the Lethbridge Collegiate Institute were the first sites in the city to receive aviation activity. In the 1920's, the City of Lethbridge obtained a license to operate a public aerodrome, south of the Exhibition Grounds, on land which is now part of the Lakeview subdivision. The latter served as a point of call on the Trans-Prairie Air Mail Service and a staging point for air services from the Prairies over the Rocky Mountains.
In 1938, the City relocated airport operations to its present site. Originally named Kenyon Field, the airport consisted of two hard-surfaced runways, connecting taxiways, runway lighting and radio and meteorological services, allowing night and day operations under all-weather conditions. Passenger services were originally provided in the Trans-Canada Airlines (TCA) hangar, currently operated by QL Aviation, which also eventually housed the airport's control tower. Regular operations commenced in October 1938, and passenger services started in April of the following year. The airport officially opened on June 7, 1939. Later that year, the Lethbridge Airport was put to use for military purposes to support the Royal Canadian Armed Forces war efforts.
In 1940, a military flying training school was established by the Department of National Defense (DND). The airport was then leased to the Government of Canada for the duration of the War and was operated as a dual civil and military aerodrome for the duration of this period. In 1947, the Department of Transportation converted the RCAF mess hall, adjacent to the current Apron 11, into the airport's Air Terminal Building (ATB), replacing the TCA passenger facility. In 1948, TCA rerouted its main service to the West Coast through Calgary, leading the city to decide against resuming airport operations and leaving them under the responsibility of the Department of Transportation (DOT). Later in the 1960's, the AT13 was converted into a combined operations-terminal building; and a new control tower was built south of Runway 05-23. The DOT assumed full ownership of the facility in 1968 and replaced the Air Terminal Building with the current facility in 1979.
During the same period, the Lethbridge Airport also played an important role in the development of Canada's regional air carrier industry. Serving as a home base to Time Air, a small regional carrier set up by Stubb Ross, a local pilot and businessman, the airport eventually became Southern Alberta's regional air service hub. Time Air initially provided service within Southern Alberta with Beach 18, Short 330 and 340 aircraft and eventually expanded its network to cover most of Western Canada with F-27 and Dash-8 aircraft.
As a result of industry deregulation and consolidation in the late 1980's, the airline was sold to Pacific Western Airlines and transformed into Canadian Regional Airlines. The carrier subsequently played an increasing role as a feeder airline to Canadian Airlines International's network and traffic focused on the latter developing hubs, mostly at Calgary and Vancouver International Airports. As a result, most of Time Air's operations were gradually shifted to Calgary in the early 1990's, leaving Lethbridge as a spoke to the Calgary hub. With declining aircraft activity, the airport's control tower was decommissioned in 1994 and subsequently demolished.
The management structure of the airport changed significantly in the 1990's with adoption of the National Airports Policy (NAP) by the Government of Canada. Under the NAP, the Federal Government relinquished ownership of regional and local airports to regional and community interests. In accordance with the provisions of this policy, the Lethbridge Airport was acquired by the County of Lethbridge on January 1, 1997 and was owned and operated by the County until July 1, 2018, when ownership was transferred to the City of Lethbridge.
Transport Canada continues to ensure safety and security at Canadian airports through appropriate policies, standards, airport certification and regulations.