William Fairfax (1691–1757) was the builder of the Belvoir estate and plantation.

William Fairfax may also refer to:

• William Fairfax (died 1514), Justice of the Common Pleas
• William Fairfax (died 1597), MP for Boroughbridge and Yorkshire
• William Fairfax (soldier) (1609–1644)
• William George Fairfax (1739–1813), vice-admiral in the Royal Navy
• Sir William George Herbert Taylor Ramsay-Fairfax, 2nd Baronet (1831–1902), of the Fairfax Baronets

See also[edit]

• George William Fairfax, planter