William Cotter

William Cotter may refer to:


 * William Richard Cotter (1882–1916), English soldier and recipient of the Victoria Cross
 * William R. Cotter (politician) (1926–1981), Democratic Party member of the United States House of Representatives from Connecticut
 * William R. Cotter (college president), lawyer and President of Colby College
 * William Cotter (bishop) (1866–1940), Irish-born Roman Catholic bishop of Portsmouth, England
 * Bill Cotter (born 1943), Irish Fine Gael politician, former TD and Senator
 * William Cotter (pirate) (1670–1702), was a pirate who once owned the Gresham Estate in Edgewater, Maryland.