Wells started in the express business as an agent for Harnden's Express, running from New York to Albany. He went on to start his own firm, Wells & Company, which ran a route from Buffalo to Detroit, the first express company to venture west of Buffalo. As a young man, William G. Fargo served as a messenger with Wells & Company, and eventually became Wells' partner. In 1850, Wells & Company joined with two other express companies to form the American Express Company with Wells serving as its president, 1850-68. American Express covered the eastern sector of the United States; Wells, Fargo & Company, formed in 1852, covered the western sector.