William John Cubit (/ˈkjuːbɪt/; born October 14, 1953) is an American football coach and former player. Cubit was the head football coach at the University of Illinois at Urbana–Champaign, first on an interim basis in the 2015 season and then promoted to the post full-time before his dismissal on March 5, 2016. Cubit served as the head football coach at Widener University from 1992 to 1996, and Western Michigan University from 2005 to 2012. Most recently, in 2019, he served as assistant head coach and running backs coach at his alma mater, the University of Delaware.