William Elliott may refer to:
- William Henry Elliott (1792–1874), British general
- William Elliott (lieutenant) (died 1792), lieutenant in the Royal Navy and marine painter
- William Elliott (engraver) (1727–1766), English engraver
- William Elliott (RAF officer) (1896–1971), senior RAF commander during WWII
- William Yandell Elliott (1896–1979), American historian and presidential political advisor
- William Elliott, Baron Elliott of Morpeth (1920–2011), British Conservative party politician, MP 1957–1983
- William J. S. Elliott, Commissioner of the Royal Canadian Mounted Police
- William Elliott (writer) (1788–1863), South Carolinian sportsman and writer
- William Elliott (politician) (1838–1907), United States Congressman from South Carolina
- William Elliott (rower) (1849–?), English professional sculling champion
- William Elliott (Peel MP) (1834–1912), member of the Canadian House of Commons representing Peel, 1878–1882
- William Elliott (Pennsylvania), Speaker of the Pennsylvania House of Representatives, 1872–1873
- William Elliott (Saskatchewan politician) (1863–1934), member of the Northwest Territories legislature 1898–1905 and Saskatchewan assembly 1905-1912
- William Elliott (Upper Canada politician) (1775–1836 or later), politician in Upper Canada
- William Elliott (Ontario politician) (1872–1944), Progressive Party member of the Canadian House of Commons
- William Elliott (aviator) (1898–1979), World War I flying ace
- William A. Elliott, art director
- William Herbert Elliott (1872–?), businessman and political figure in Ontario
- Will Elliott (born 1979), Australian horror fiction writer
- Sir William Elliott (RAF officer) (1896–1971), senior Royal Air Force commander