William Duffy
# William Duffy

William Duffy, Bill Duffy or Billy Duffy may refer to:

* Bill Duffy (basketball), American basketball player and player agent
* Bill Duffy (sportsman) (1866–1959), Australian sportsman
* Billy Duffy (born 1961), English musician
* Billy Duffy (hurler) (1931–2005), Irish hurler
* William Duffy, a pseudonym of William Dufris (1958–2020), an American voice actor
* William Duffy (bishop), English Roman Catholic bishop
* William Duffy (politician) (1865–1945), Irish nationalist politician
* William James Duffy (1888–1946), Canadian politician
* William J. Duffy (1916–2013), American jurist and legislator
