William Mahony

William Mahony may refer to:


 * William Mahony (politician, born 1877) (1877–1962), member of the Australian House of Representatives, 1915–1927
 * William Mahony (New South Wales politician) (1856–1918), member of the New South Wales Legislative Assembly, 1894–1910
 * William Mahony (bishop) (1919–1994), Bishop of the Roman Catholic Diocese of Ilorin
 * Bill Mahony (William Victor Mahony, born 1949), Canadian Olympic swimmer