For some of the earliest bus companies, listed in early reports of the California Railroad Commission, a first year or decade of operations is listed.
Additional bus companies, listed as existing during additional years or decades, are mentioned in old City Directories, and in the WPA American Guide Series of state guidebooks.
Gate City Bus Line - existed in 1940's.
Highland-Patton Bus Lines - connected San Bernardino with Highland and Patton. Also existed in 1940's.
Lee's Auto Stage Line - began operations by 1920's, served San Bernardino, Rialto, Bloomington.
Mountain Auto Line - served Crestline, Lake Arrowhead, Big Bear Lake. Also existed in 1940's.
Twenty Nine Palms Stages - served Twenty Nine Palms, Joshua Tree, Yucca, Morongo Valley.