William, Bill or Billy Holmes may refer to:
Sports
- Bill Holmes (William Orser Holmes, 1899–1961), Canadian ice hockey player
- Bill Holmes (footballer, born 1926), English footballer
- Billy Holmes (footballer, born 1875) (1875–?), English footballer with Manchester City who became manager of Clapton Orient
- Billy Holmes (footballer, born 1951) (1951–1988), English footballer with Hereford United, Wimbledon and other clubs
- Billy Holmes (Australian footballer) (1890–1942), Australian footballer for Collingwood and Fitzroy
- William Holmes (cricketer) (1885–1951), English cricketer
- William Holmes (cyclist), British Olympic cyclist
- William Holmes (footballer) (1889–1933), footballer who played for Stoke
Politicians
- Bill Holmes (trade unionist) (1873-1961), British Labour Party politician and trade unionist
- William Holmes (MP) (1779–1851), British Tory politician
Military
- William Holmes (Australian general) (1862–1917), Australian Major General of World War I
- William Holmes (British Army officer) (1892–1969), British Lieutenant General of World War II
- William Edgar Holmes (1895–1918), English recipient of the Victoria Cross
- William Holmes (Surgeon-General) (1762–1834), Surgeon-General to the British Forces in Canada
- William Norman Holmes (born 1896), World War I flying ace
Others
- William Holmes (academic) (1699–1768), Vice-Chancellor of Oxford University 1732–1735
- William Holmes (actor), appeared in the 1952 film The Bushwackers
- William Holmes (anarchist), US anarchist in the late 19th century and contributor to Free Society
- William Holmes (film editor) (1904-1978), American film editor
- William Hardy Holmes (1873–1951), Anglican bishop
- William Henry Holmes (1846–1933), American anthropologist
- William Henry Holmes (musician) (1812–1885), English musician