The origin of transporting packages by air for UPS (then United Parcel Service) dates to 1929; much like the U.S Postal Service, UPS packages were transported as baggage on commercial airline flights. Many packages were shipped by the Ford Trimotors of United Airlines. After Black Tuesday and the beginning of the Great Depression, the air service would be discontinued by the end of 1931. However, the air service would lead to the expansion beyond the West Coast; in 1930, the company moved operations from Oakland to New York City and established operations in other regions across the country as well.

After World War II, UPS (in the process of acquiring common carrier rights for every address in the United States) revisited the idea of shipping packages by air. Starting in 1953, 2-day delivery was offered on coast-to-coast packages; the service was called Blue Label Air. As before, volume was transported via commercial flights. Initially unprofitable, Blue Label Air became popular as its speed created enough demand to maintain a profit.

In 1975, UPS started its first international operations as it moved into Canada. The following year it started a service into Germany. As UPS had become a truly international company, the need for its own fleet of aircraft was becoming more clearly apparent, rather than relying on commercial flights. Additionally, competitor Federal Express, with its own jet fleet, was making inroads on UPS and had become profitable for the first time in 1976. In 1978 the Airline Deregulation Act gave UPS a significant opportunity: the company could now establish its own airline and flying from city to city would require far fewer legislative hurdles as the federal government now encouraged competition between airlines. In 1980 UPS opened its first major hub, located in Louisville, Kentucky. The location was chosen largely because it is no more than three hours flying distance (by jet) from the majority of the continental United States. In addition, Louisville has relatively mild weather and is at the westernmost point of the Eastern time zone. Also in the early 1980s the company began acquiring a fleet of jet aircraft recently retired from commercial aircraft duty comprising Douglas DC-8s, Boeing 727-100s and Boeing 747-100s.

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