William Pitt most commonly refers to:
William Pitt, 1st Earl of Chatham (1708–1778), British statesman; often known as William Pitt the Elder
William Pitt the Younger (1759–1806), his son and Prime Minister of Great Britain (1783–1801 and 1804–1806)
William Pitt may also refer to:
William Pitt (courtier) (1559–1636), English courtier and politician who sat in the House of Commons (1614–1625)
William Augustus Pitt (c. 1728–1809), British general
William Pitt Kalanimoku (1768–1827), chief minister to King Kamehameha I
William Pitt Leleiohoku I (1821–1848), son of Kalanimoku
John William Pitt Kinau (1842–1859), prince of Hawaii and son of Leleiohoku I
William Pitt Leleiohoku II (1854–1877), Crown Prince of Hawaii
William Baker Pitt (1856–1936), founder of Swindon Town F.C. and Catholic prebendary
William Fox-Pitt (born 1969), English equestrian
William Morton Pitt (1764–1836), British politician and MP for Poole (1780–1790) and Dorset (1790–1826)
William Rivers Pitt (born 1971), left-wing American essayist
William Pitt (architect) (1855–1918), Australian 19th-century architect
William Pitt (engineer) (1840–1909), Canadian inventor of the underwater cable ferry in the early 1900s
William Pitt (Mormon) (1813–1873), early Mormon bandleader
William Pitt (ship-builder) (died 1840), author of The Sailor's Consolation
William Pitt (cricketer) (1800–1871), English cricketer
Bill Pitt (politician) (born 1937), British politician and MP for Croydon North West (1981–1983)
Bill Pitt (racing driver), Australian racing driver and motor racing official
Brad Pitt (born 1963), American actor
William Pitt (singer), American singer
