In addition to changing its name, United Parcel Service continued to develop new approaches to its operations. In 1922, the company acquired a business in Los Angeles that offered "wholesale delivery" service, shipping products from the manufacturer to the distributor. This section of the company quickly began providing its product transportation services to the public, in the same way that the U.S. Postal Service did. This was known as common carrier service. The acquisition of common carrier rights enabled the company to deliver packages to private and commercial customer addresses. This step placed UPS in direct competition with the USPS. The offerings included daily pickups, cash-on-delivery payment acceptance, automatic return of undeliverable packages, and weekly billing, all at rates competitive with the post office. Common carrier services began slowly at UPS, spreading first throughout southern California.
The 1920s marked a period of technological and service innovation. A major new development occurred in 1924, when the company introduced an innovative conveyor belt system used for package handling. Then in 1929, UPS began to offer air service through private airlines. The economic downturn in the U.S., along with a lack of volume, led to the end of the service two years later.
Geographic expansion emerged as a bold new opportunity for the company. Through the end of the 1920's, UPS expanded its retail delivery service to encompass all major cities along the coastline of the Pacific U.S., including San Francisco, San Diego and Portland, Oregon. In spite of the economic conditions after the U.S. stock market crash of 1929, UPS expanded eastward the following year, opening operations and moving its headquarters to New York City.