Keys & Miller Lumber Company were dealers in lumber, grain, hay, lime, fertilizers, and coal. Located in Elkton, Maryland, the company incorporated in 1892 with the following partners: S. Kennard Miller (1840-1896), Samuel J. Keys (1845-1924), Isaac D. Davis (1841-1920), Thomas B. Miller (1864-1945), and William J. Davis (1871-1933).

The original company began in 1872 as Davis & Miller when S. Kennard Miller and Col. Isaac Davis formed a partnership and started in the lumber business. Soon after, Keys moved from Vienna, Maryland, to Elkton, Maryland, and joined the company; when Miller retired in ill health, the firm became Davis, Keys & Company. In 1892, S. Kennard Miller's son, Thomas B. Miller, joined the company, and it was reorganized and incorporated as Keys & Miller Lumber Company.

Keys was president until his death in 1924. Isaac Davis left the company around 1900 and became cashier, and later director, of the Second National Bank of Elkton. Isaac Davis's son, William J. Davis, became president after Keys, and was president until his death in 1933. Thomas B. Miller eventually left the lumber business and became president of the First National Bank of Elkton.

By 1974, Keys & Miller was listed among the companies given notice from the Executive Department of Annapolis, Maryland, Governor's proclamation giving notice of forfeiture of the charter of the delinquent corporation.