William Aldrich (January 19, 1820 – December 3, 1885) was a Republican United States Representative from the state of Illinois. He was born in Greenfield Center in the Town of Greenfield in New York. He attended local schools and taught school himself. Aldrich moved to Michigan and then to Two Rivers, Wisconsin where he worked as a shopkeeper and manufacturer. He served as superintendent of schools from 1855 to 1856 and chairman of the county board of supervisors from 1857 to 1858. In 1859 he was elected to the Wisconsin State Assembly. He moved to Chicago, Illinois in 1861 and opened another shop. He served as congressman from 1877 to 1883 after having earlier served in the Chicago City Council in 1876.Aldrich died in Fond du Lac, Wisconsin. He is buried in Rosehill Cemetery in Chicago.