Smith, a junior, posted his intentions to transfer Tuesday on Twitter. He thanked Louisiana-Monroe coach Matt Viator and offensive coordinator Matt Kubik for their support.
Smith leaves with 3,854 career passing yards, 31 touchdowns and 21 interceptions in 17 starts.
Injuries cost Smith nine games as a redshirt freshman and sophomore and opened the door up for sophomore Caleb Evans. Evans beat out Smith for the quarterback spot in fall camp and turned in the sixth-best season in school history.
Smith made one start, against Southern Miss, and appeared sporadically throughout the 2017 season.
There's no word on where Smith is headed.