William Kidd (1645–1701) was a Scottish sailor and pirate commonly known as Captain Kidd
William, Bill or Billy Kidd may also refer to:
- William Kidd (painter) (1796–1863), Scottish painter
- Billy Kidd (footballer) (1908–1978), English footballer
- William Matthew Kidd (1918–1998), United States federal judge
- Billy Kidd (born 1943), American ski racer
- Bill Kidd (American politician) (born 1952), member of the Missouri House of Representatives
- Bill Kidd (born 1956), Scottish National Party politician
- Billy Kidd (American football) (born 1959), American football center
- William Kidd (composer) (fl. 1987–2012), American musician, orchestrator, and composer