Scholes approached United boss Sir Alex Ferguson to reverse his decision, made at the end of last season, to retire.
Scholes is currently on the bench for the FA Cup third round clash with Manchester City.
Ferguson said: “It’s fantastic that Paul has made this decision. It’s always sad to see great players end their careers, but especially so when they do it early.
“But he has kept himself in great shape and I always felt that he had another season in him. It’s terrific to have him back.”
Paul Scholes added: “I’ve been pretty clear since I stopped playing that I miss it. I’m delighted the manager feels I can still make a contribution to the team and I’m looking forward to playing my part in trying to bring more success to this great club.”
