Ander Herrera scored the winner as Manchester United advanced into a record-equalling 20th FA Cup final at the expense of Tottenham at Wembley Stadium here.
Spurs on Saturday suffered their eighth successive defeat in the FA Cup semifinals and left manager Mauricio Pochettino to continue to wait for his first trophy in the north London club, Xinhua news agency reported.
England forward Dele Alli put Tottenham ahead after only 11 minutes, sliding home a finish from Christian Eriksen's cross.
Jose Mourinho's side levelled on 24 minutes when Alexis Sanchez rose high to head Paul Pogba's cross past Spurs keeper Michel Vorm.
The former Arsenal striker created the winner in the 62nd minute, holding off Kieran Trippier and sending the ball into the box where Jesse Lingard set up Herrera for a low finish.
Mourinho, who lifted the League Cup and Europa League in his first season at Manchester United last term, was delighted after the match. "We deserve it. If we split the match into periods we were the best team for many of these periods. Even when they had the ball when we were winning we were totally in control."
Pochettino said: "I think every defeat is bad. It's difficult to accept but of course, we are disappointed we are out and cannot achieve the final.
"We competed but not enough to win. We dominated the first half and were much better than Manchester United.
"To win a trophy when you face a side like Manchester United, Chelsea or Manchester City is not easy. But the most important thing is we are able to compete."
Manchester United will fight for the FA Cup title against the winner of the other semifinal between Chelsea and Southampton, which will be played on Sunday.