William Capell

William Capell may refer to:

• William Capel (died 1515), Lord Mayor of London
• William Capell, 3rd Earl of Essex (1697–1743), 3rd Earl of Essex
• William Capell, 4th Earl of Essex (1732–1799), 4th Earl of Essex
• William Capel (sportsman) (1775–1854), sportsman and priest
• William Jennings Capell (born 1952), American heir presumptive to the earldom of Essex