William Haines (1900–1973) was an American movie actor who later became a designer of furniture and interiors.
William Haines may also refer to:
William Haines (artist) (1778–1848), English engraver and painter William Haines (Australian politician) (1810–1866), Australian politician William Haines (South Australian politician) (1831–1902), S.A. pioneer William T. Haines (1854–1919), Governor of Maine from 1913 to 1915 William Henry Haines (1811–1884), English painter William Wister Haines (1908–1989), American novelist C. William Haines (1928–1996), American politician in New Jersey Willie Haines (1900–1974), Portsmouth and Southampton footballer