In his announcement, Bridges thanked Spartans coach Tom Izzo and others for "giving a skinny kid from Flint a chance to play at such a legendary program."
He confirmed a widely expected decision to enter the draft and that he's signing with agent Rich Paul from Klutch Sports. ESPN draft analyst Jonathan Givony projects Bridges as the No. 11 prospect in his latest NBA draft rankings.
He averaged 17.1 points, 7.0 rebounds and 2.1 assists as a sophomore this season, becoming the 11th consensus All-American at Michigan State during Izzo's tenure.
Bridges is among the 10 semifinalists for the Naismith Trophy and among the five finalists for the Julius Erving Small Forward of the Year Award.
"Miles wanted to come back to school this year because he loved Michigan State, he loved his teammates and friends and he loved being part of this community," Izzo said in a statement. "I think I speak for all of Spartan Nation in thanking him for how he represented us and for all of the great things he helped us achieve.
"He's given us everything we could ask for and so much more. Miles is a mature young man who has excelled on the court and has been an exemplary student. I think he's ready to handle being a pro basketball player both on and off the court. More than anything, he conducted himself with the utmost class and humility. As his coach, it's a thrill for me to see him getting the chance to live his dream and I look forward to following his career in the NBA."
Bridges earned Big Ten Freshman of the Year honors in 2016-17, when he averaged 16.9 points, 8.3 rebounds and 2.1 assists.