It was formed by the merger of three companies: Chicago Motor Bus Company, the Chicago Stage Company, and the Depot Motor Bus Lines, sometime in the early 1920s. By 1922 it had become the second-largest urban bus company in the United States, and was purchased by John D. Hertz, who owned the Yellow Cab Company and auto dealerships in Chicago. Two years later, Hertz purchased New York's Fifth Avenue Coach Company and created a holding company, The Omnibus Company, to control the two.
CMCC was known as an operator of double-decker buses, in common with Fifth Avenue Coach.
CMCC's operations were taken over by the Chicago Transit Authority on October 1, 1952.
Currently, a tour bus operator has revived the name of Chicago Motor Coach Company, but there is no relation between the two companies, though the company uses double-decker buses and thus considers it as a revival of the older company.