Lincoln Bus Line - connected Stockton with Lincoln district, acquired in 1966 by San Joaquin Regional Transit District.
Newton Passenger Transportation Co. - served Stockton and suburbs, replaced in 1956 by Stockton City Lines.
Service Bus Line - served Stockton, Escalon, Modesto.
Additional information on transit in Stockton is available in the September-October 1987 issue of the magazine "Motor Coach Age".