Sources told ESPN that the 33-year-old Noah, who had two years remaining on his deal, had no traction on an open roster spot elsewhere in NBA and remained unwilling to agree to a buyout.
The Knicks can now spread the remaining $37.8 million balance of Noah's contract into smaller cap hits over the next three years.
Knicks general manager Scott Perry had been attempting to move Noah since prior to last February's trade deadline, but he has been cautiously unwilling to include the necessary assets -- a good young player, or a future first-round pick or picks -- to make Noah's contract palatable to another team.
Talks continued through the summer, but New York never came close to finding a deal to unload Noah, league sources said. Using the stretch provision after Aug. 31 reduces Noah's cap hit to $6.4 million, saving the team $12.9 million toward the salary cap. Stretching his contract after Sept. 1 costs the Knicks $6.4 million in cap space in the summers of 2020 and 2021.
The $18.5 million salary for 2018-19 still counts toward the Knicks' salary cap.
In addition to Noah, the Knicks also waived Jeff Coby and Kadeem Allen.