Kanter had referenced his decision earlier Friday afternoon on Twitter.
— Enes Kanter (@Enes_Kanter) June 29, 2018
ESPN reported on Thursday that Kanter would opt in unless there was a significant change in the free-agent market.
With Kanter on the roster for the 2018-19 season, the Knicks will have limited money to offer free agents this summer.
New York is currently projected to have an $8.6 million non-tax midlevel exception and a $3.4 million biannual exception to offer 2018 free agents.
Kanter will likely start at center for New York next season. He averaged 14 points and 11 rebounds in 71 starts for the Knicks, who finished the season 23-59.
According to ESPN Stats & Information, Kanter was the first Knicks player to average a double-double since Tyson Chandler in 2012-13, Chandler’s only All-Star season. Kanter finished fourth in the NBA in offensive rebounds per game with 3.8.