On June 23, 2016, Jackson was selected by the Boston Celtics with the 45th overall pick in the 2016 NBA draft. On July 27, 2016, he signed with the Celtics. On November 6, he made his professional debut in a 123–107 loss to the Denver Nuggets, recording eight points, three rebound and two assists in 11 minutes off the bench. During his rookie season, he has received multiple assignments to the Maine Red Claws, the Celtics' D-League affiliate. On July 15, 2017, Jackson was waived by the Celtics.