| Current position | |
|---|---|
| Title | Head coach |
| Team | Stony Brook |
| Conference | CAA Football |
| Record | 7–2 |
| Biographical details | |
| Born | March 5, 1992 Minneapolis, Minnesota, U.S. |
| Playing career | |
| 2010 | Kansas State |
| 2011 | James Madison |
| 2012 | Butler (KS) |
| 2013–2014 | Houston |
| Position(s) | Quarterback |
| Coaching career (HC unless noted) | |
| 2015 | Concord (QB) |
| 2016–2017 | Indiana (GA) |
| 2018–2019 | VMI (WR) |
| 2020–2021 | VMI (OC/QB) |
| 2022 | Richmond (OC/QB) |
| 2023 | Western Michigan (OC/QB) |
| 2024–present | Stony Brook |
| Head coaching record | |
| Overall | 7–2 |
William Cosh (born March 5, 1992) is an American college football coach. He is currently the head football coach for Stony Brook University.