Carrick has signed a deal that will keep him at Old Trafford until the summer of 2015, with the option of a further year.
The midfielder's previous contract was due to expire at the end of the current season.
Carrick said: "It's great to extend my contract at this club. I am really enjoying my football.
"The club has gone through a few changes and working under David Moyes has been fantastic. I have won many trophies in my years playing here and I am looking forward to achieving more in the future."
United manager David Moyes said: "I am delighted Michael has extended his contract. During my short time at the club it hasn't been hard to notice that Michael is a great reader of the game and has excellent passing ability.
"He is an exceptional man and a true professional and it's great that he has committed himself to the club."