William Milligan (disambiguation)

William Milligan (1821–1892) was a Scottish theologian.

William or Billy Milligan may also refer to:

• William Lane Milligan (1795–1851), British military surgeon
• William Milligan, Lord Milligan (1898–1975), Scottish politician and judge
• Billy Milligan (1955–2014), American multiple personality
• Billy Milligan (baseball) (1878–1928), American baseball player
• ST1M (born 1986), Russian rapper also known as Billy Milligan