William T. Smith (1916–2010) was an American farmer and politician from New York. William T. Smith may also refer to:
William Trickett Smith (1937–2021), American lawyer who was disbarred William Trickett Smith II (born 1981), his son, American drug trafficker convicted of murdering his wife in Peru in 2007 William Thomas Smith (1896–1994), World War I flying ace William Tyler Smith (1815–1873), English obstetrician, medical writer and journalist William T. "Wee Willie" Smith (1911–1992), American professional basketball player
See also William Thompson Russell Smith (1812–1896), Scottish-American painter William Twigg-Smith (1883–1950), New Zealand artist