Stidham, a sophomore who started three games for the Bears in 2015, revealed his decision to leave with a post on his Twitter account.
Interim Baylor coach Jim Grobe confirmed Stidham's decision to leave in a radio interview Thursday with ESPN 1660 in Waco, Texas.
"It's always hard when you have two really talented quarterbacks, because they both want plenty of snaps. Last year, we weren't able to give Jarrett enough snaps, though some injuries affected that," Grobe said. "I don't think he was happy backing up Seth Russell, and so he's decided to move on and try to find a place where he can get more snaps."
Stidham's next destination is unclear, though it's possible he could enroll at a junior college for the fall semester. That move would permit him to make an unrestricted transfer to play for any other program in 2017.
As a true freshman, Stidham threw for 1,265 yards and 12 touchdowns with only two interceptions in 10 games. When Russell went down with a season-ending neck injury in October, Stidham took over as Baylor's starter and led the Bears to a road win over Kansas State in his first career start.
But Stidham's freshman season came to an end in November, when he suffered a broken ankle bone in a win over Oklahoma State. While Russell recovered from his injury in 2016, Stidham was Baylor's No. 1 QB for several weeks in practice this spring. Their coaches did not officially name a starter at the end of spring, though Russell has since been fully cleared for contact.
A former ESPN 300 recruit, Stidham hails from Stephenville (Texas) High School, where ex-Baylor coach Art Briles was coach from 1988-1999. Stidham flipped from Texas Tech to Baylor late in his recruitment.
Briles was suspended with intent to terminate on May 26 and reached a contract settlement with Baylor on June 17.
With Stidham gone, true freshman Zach Smith becomes Baylor's top backup behind Russell. Smith enrolled in the program in January.
In the interview with ESPN 1660, Grobe acknowledged Baylor's roster is comprised of about 70 players -- well short of the 85-man limit. A total of 12 signees from the Bears' top-20-rated recruiting class will not be a part of the program this fall. Grobe said the team also lost four players for medical reasons and a few more who had academic or disciplinary issues.