The move creates about $4.1 million in salary-cap space, nearly doubling the Patriots' total cap space to about $9 million.
Van Noy was scheduled to count $7.3 million against the team's cap, which was the ninth-highest figure among players.
Van Noy, who turns 31 on March 26, had signed a two-year, $12 million contract with the Patriots in March 2021 (with $6 million guaranteed). It marked his second stint with the franchise after he'd been part of two Super Bowl championship teams from 2016 to 2019 before signing with the Miami Dolphins in 2020.
The 6-foot-3, 250-pound Van Noy played in 16 regular-season games last season in New England, totaling 66 tackles to rank fourth on the team. He also had five sacks (second on the team) and 10 passes defended in addition to a forced fumble and interception returned for a touchdown.
Van Noy's versatility to play both on and off the line of scrimmage added to his value in the Patriots' multiple scheme. The defense sputtered down the stretch, ending with a 47-17 playoff loss to the Buffalo Bills in which the unit didn't force a punt.
He had acknowledged the possibility he wouldn't return in an interview on sports radio WEEI on March 2 when he said: "There are a lot of decisions to be made ... I'm under contract for one more year, but you never know."