Hoyer will join a crowded quarterback room in New England that consists of Cam Newton, 2021 first-round draft pick Mac Jones and third-year signal-caller Jarrett Stidham.
The 35-year-old Hoyer, who visited with the AFC East rival New York Jets earlier this off-season, began last season as the Patriots' top backup behind Newton before slipping to the No. 3 spot behind Stidham.
Hoyer was unexpectedly thrust into a starting role before the Patriots' Week 4 road game against the Kansas City Chiefs after Newton tested positive for COVID-19. New England lost 26-10 in that matchup, with Hoyer recording 130 passing yards and an interception.
Hoyer has notched 10,404 passing yards with 52 touchdowns and 35 interceptions in 70 career NFL games with the Arizona Cardinals, Cleveland Browns, Houston Texans, Chicago Bears, San Francisco 49ers, Indianapolis Colts and Patriots.
His best season came in 2015 with the Texans, when he had 2,606 yards and a career-best 19 touchdowns through the air.