William Irwin
William Irwin, Will, Bill, or Billy Irwin may refer to:
Law and politics
- William W. Irvin or Irwin, American politician in Ohio
- William W. Irwin, American politician in Pittsburgh, Pennsylvania
- William Irwin (California politician), American politician in California
- William Irwin (Unionist politician), Unionist politician in Northern Ireland
- Bill Irwin (politician), American politician in Missouri
Sports
- Bill Irwin (baseball), American baseball player
- Billy Irwin (Australian rules footballer), Australian footballer
- Bill Irwin (skier), Canadian skier
- Bill Irwin (footballer), Northern Irish footballer
- Bill Irwin (wrestler), American professional wrestler
- William Irwin (boxer), Canadian boxer
Others
- Will Irwin, American journalist
- William [Andrew Irwin], Canadian theologian
- William Roy Irwin, Canadian-born World War I flying ace
- William Arthur Irwin, Canadian journalist and diplomat
- William C. K. Irwin, American pianist, conductor, and songwriter
- Bill Irwin (priest), Canadian priest
- Bill Irwin, American actor and clown
- William Irwin (philosopher), American professor of philosophy