The 20-year-old spent the second half of last season on loan at Stockport County, although he only represented the club on one occasion, which came against Tranmere Rovers in League Two.
Bennett is not in Erik ten Hag's plans at Man United for the 2024-25 campaign, and a loan switch to Fleetwood for the remainder of the season has now been announced by the Red Devils.
"Manchester United defender Rhys Bennett is to spend the 2024/25 season on loan at Fleetwood Town," read a statement on the Premier League club's official website.
"The FA Youth Cup-winning captain, who scored in the 2022 final victory against Nottingham Forest at Old Trafford, has joined the League Two side for the campaign and could make his debut in Saturday's game at AFC Wimbledon."
Bennett, who will wear the number 15 shirt for Fleetwood, travelled with the Man United squad on their pre-season tour of the United States, featuring against Arsenal and Liverpool in friendlies over the summer.
Man United are soon expected to confirm Scott McTominay's move to Napoli, while Jadon Sancho could also leave the 20-time English champions before the transfer window closes for business.