Sir William Charters Patey, KCMG (born 11 July 1953) is a British retired diplomat. He was British Ambassador to Afghanistan from 2010 to 2012, and previously served as Ambassador to Sudan, to Iraq and to Saudi Arabia. He retired from HM Diplomatic Service in April 2012 and was replaced by Sir Richard Stagg, formerly British High Commissioner to India. He has since worked in business.