The head coach and the Patriots agreed to part ways with one another after 24 seasons on Thursday, this according to multiple reports.

New England has not yet confirmed the news ... though it did announce Belichick and owner Robert Kraft will hold a press conference later Thursday afternoon, presumably to talk all about the decision.

Belichick first joined Kraft's Patriots in the 2000 season ... and it didn't take long for him to build one of the greatest dynasties in sports history.

In 2001, he won his first Super Bowl with the team. He repeated the feat twice more in 2003 and 2004. He later won three more rings with the org. too.

Almost all of his success came with Tom Brady under center -- though when the best quarterback of all-time bolted for Tampa Bay, Belichick's teams suffered.

In his first year without Tom in 2020, Belichick went 7-9. In the ensuing three years, his teams were just 22-29 (including a 4-13 record this season).

Belichick went 266-121 overall in his New England career ... and he leaves Foxborough just 14 wins away from tying Don Shula's all-time mark of 347 wins by a head coach.

No word yet where either side will go from here. Reportedly, assistant coach Jerod Mayo -- a former star with the Patriots -- is a leading candidate for the job ... though ex-New England linebacker and former Titans head coach Mike Vrabel will no doubt get a long look for the gig as well.

As for Belichick, it's unclear whether he'll retire or coach somewhere else ... though many have speculated a spot like the Los Angeles Chargers could be a good fit for him.