William Fletcher may refer to:
Politics and law William Fletcher (Irish judge) (1750–1823), Irish politician and justice of the Court of Common Pleas William A. Fletcher (Michigan judge) (1788–1852), chief justice of the Michigan Supreme Court William Fletcher (English politician) (1831–1900), British member of parliament for Cockermouth, 1879–80 William Meade Fletcher (1870–1943), American lawyer, professor and judge William A. Fletcher (born 1945), United States federal appeals court judge
Religion William Roby Fletcher (1833–1894), English-born Australian Congregational minister and vice-chancellor of the University of Adelaide William Fletcher (priest) (died 1926), Welsh Anglican priest
Science William Fletcher (engineer) (1848–1918), British author and steam traction engine designer William Fletcher (physician) (1872–1938), English doctor William Whigham Fletcher (1918–2001), Scottish botanist William Thomas Fletcher (born c. 1935), American mathematician
Sport William Fletcher (rugby union) (1851–1895), English rugby international William Fletcher (cricketer) (1866–1935), English cricketer for Yorkshire William Fletcher (rower) (1869–1919), English rower and coach Will Fletcher (born 1989), British rower
Other people William Fletcher (valet) (c. 1775–1839), servant of Lord Byron William Andrew Fletcher (1839–1915), American author and lumber tycoon William I. Fletcher (1844–1917), American librarian, bibliographer and indexer William Bartlett Fletcher Sr. (1862–1957), admiral in the United States Navy William John Bainbrigge Fletcher (1879–1933), British consul and author of books on Chinese poetry
Fictional characters Billy Fletcher, a fictional character in the British soap opera Emmerdale Will Fletcher (The Bill), a fictional character in the British TV drama series The Bill