On August 28, 1907, teenagers James E. Casey and Claude Ryan founded the American Messenger Company in Seattle with a $100 loan, carrying messages on foot, by bicycle and by streetcar. As telephones spread they shifted to retail parcels, bought a Ford Model T in 1913 and merged with Evert McCabe’s company to form Merchants Parcel Delivery, which pooled many stores’ packages on one vehicle. After expanding to Oakland in 1919 they became United Parcel Service, began gaining common carrier status in Los Angeles in 1922 and reached New York City by 1930.

An air service tried in 1929 died in the Depression, but Blue Label Air launched in 1953, and in 1975 UPS became the first package company to serve every address in the 48 contiguous states. UPS Airlines followed in 1988, the 1991 DIAD handheld added real-time tracking, and the company staged the largest IPO of the 20th century in November 1999 before buying Mail Boxes Etc. in 2001. Amazon paid UPS $11.3 billion in 2020, over 13% of revenue, yet UPS later cut Amazon volume to focus on healthcare logistics, buying Bomi Group and MNX.

• Worldport at Louisville Muhammad Ali International Airport covers 5.2 million square feet and sorts 115 packages a second.
• Casey wanted yellow trucks until partner Charlie Soderstrom suggested the dirt-hiding brown of Pullman railroad cars.
• Retired delivery trucks are never resold: they are stripped, painted over and crushed under company supervision.
• A 16-day Teamsters strike in 1997 under Ron Carey shut UPS down nationwide.
• The 2023 contract set $21 starting pay for part-time workers and added air conditioning to new delivery vans from 2024.