The Scotland international has become a key player at Old Trafford since moving through the trainee ranks.
Fletcher said: “I can’t imagine being anywhere else. For me there is nowhere better than United and if I can play my whole career at this club, I’ll be a very happy man.
“Everything about the club from the fans, the facilities, right through to the structure is just fantastic and I wouldn’t want to be anywhere else – and there is something very special about staying at one club for your whole career.
“Gary Neville, Paul Scholes and Ryan Giggs are all legends at Old Trafford and to get anywhere close to that would, for me, be a real achievement.”
