Jim McBride of the Boston Globe reported Newton was released on Tuesday, ahead of the 4 p.m. ET deadline for teams to cut their rosters down to 53 players.
There was plenty of mystery throughout training camp and the preseason about who New England's starting quarterback would be.
In the first week of training camp, Belichick told reporters that Newton was in position to start, but he would continue to evaluate things.
"We'll take a look at the whole situation," he said. "I don't think you want to evaluate players at any position off one or two plays, or maybe a day. So from a consistency standpoint, that's always important. And obviously production. So hopefully those things will be good, and I'm sure it will be a hard decision."
Despite Belichick's comments, Newton told reporters on Aug. 16 that the Patriots coach hadn't told either quarterback anything.
"No. You know he hasn't said that. So for you to just ask that question, you know, it is what it is," he said. "Every single day, I'm coming out here with the anticipation to just get better, and that's the only thing that I can do. So I can control that."
Both Newton and Jones played well in New England's second preseason game against the Philadelphia Eagles. Newton, who started the game, finished 8-of-9 for 103 yards and one touchdown. Jones went 13-of-19 for 146 yards in relief.
There did appear to be an opening for Jones to win the job on Aug. 23 when the Patriots announced that Newton had to stay away from the club for four days due to a "misunderstanding" about COVID-19 tests conducted away from team facilities.
Belichick told reporters on Aug. 26 that Newton didn't violate any team rules related to the testing misunderstanding.
Newton started each of New England's three preseason contests, though he only played two drives against the New York Giants on Sunday. He finished 2-of-5 for 10 yards and one interception.
Jones, on the other hand, went 10-of-14 for 156 yards and a touchdown in the Patriots' 22-20 win.
Newton re-signed with the Patriots on a one-year, incentive-laden deal in March. The 32-year-old had a difficult first season in New England. He threw for 2,657 yards, ran for 597 yards, accounted for 20 touchdowns and 10 interceptions with a 65.8 completion percentage.
New England added competition in its quarterback room by selecting Jones with the No. 15 pick in the 2021 NFL draft. The Alabama star was the best signal-caller in college football last season, finishing third in Heisman Trophy voting.
The Patriots also got aggressive in free agency with the hope of improving on last year's 7-9 record. They signed wide receivers Nelson Agholor, Kendrick Bourne and tight ends Hunter Henry and Jonnu Smith to boost the passing game.
Jones led the nation with 4,500 passing yards and a 77.4 completion percentage. He finished second with 41 touchdown passes.
Given how different Newton and Jones are as quarterbacks, the Patriots could have kept both and tried to use them in different packages.
Instead, Belichick and offensive coordinator Josh McDaniels are prepared to turn the offense over to Jones right out of the gate against the Miami Dolphins on Sept. 12.