William McCoy
William McCoy or MacCoy may refer to:
- W. F. McCoy, Speaker of the Northern Ireland House of Commons
- William McCoy (rum runner), American rum-runner during Prohibition
- William McCoy (congressman), American politician and member of Congress
- William McCoy (mutineer), Scottish mutineer on HMS Bounty
- William McCoy (Oregon politician), American politician and member of the Oregon Legislative Assembly
- William D. McCoy, American diplomat
- William F. MacCoy, lawyer and politician in Nova Scotia, Canada
- William J. McCoy (composer), American composer
- William J. McCoy (Mississippi politician), American politician and Speaker of the Mississippi House of Representatives
- William John McCoy, American politician and member of the Wisconsin State Assembly
- Willie McCoy (rapper), rapper
- Bill McCoy (cricketer), New Zealand cricketer