William Addison may refer to:
William Addison (physician) (1803–1881), British physician William Addison (VC) (1883–1962), holder of the Victoria Cross William Addison, 4th Viscount Addison (born 1945), British Conservative peer William Addison (chess player) (1933–2008), American chess master William Fountaine Addison (1817–1893), clergyman, Canon of Gibraltar, father of Robert Brydges Addison William Grylls Addison (1853–1904), English landscape painter, brother of Robert Brydges Addison William Wilkinson Addison (1905–1992), English historian and jurist Will Addison (born 1992), English-born Irish rugby union player