The 29-year-old left-back joined the Reds in January 2006 and has made 226 appearances, scoring three goals. He has won three Premier League titles, three League Cups including one as captain in 2010 and winners' medals in both the Champions League and the Club World Cup.
“Ever since I arrived at United, it’s been a dream come true playing here,” Evra told ManUtd.com. “The fans, the players, the manager and the staff all work hard to make this club the best in the world.
“I’ve won a lot in the last five years, but I want to win more and I know that’s the mentality of everyone here.”
The deal secures the services of a player Sir Alex Ferguson describes as “unquestionably one of the world’s best left backs”.
The boss added: “Patrice has developed into a key character in the dressing room. It’s great that he’s committed himself to Manchester United. His experience and talent will be increasingly important to us.”