United said Mata, whose current deal was set to expire this month, had agreed to remain with the 20-times league champions for two more years with the option to extend for another year.
"It is a real honour to continue to represent this amazing club and our incredible fans. I have been at Manchester United for five years and I am proud to call Old Trafford my home," Mata said in a statement https://www.manutd.com/en/news/detail/juan-mata-signs-new-contract-to-stay-at-man-united on the club's website.
Mata said United manager Ole Gunnar Solskjaer had a "truly exciting vision" for the club as they look to improve on their disappointing sixth-placed finish last season.
"I'm looking forward to working with Ole and his fantastic coaching staff. The vision that they have for the club is truly exciting and I'm so happy I'll be a part of that," he said.
Mata has made 218 appearances for United in all competitions, scoring 45 goals and has won the FA Cup, a League Cup and the Europa League.
"Juan is the ultimate professional and one of the most intelligent players I have worked with," Solskjaer said.
"He's a great example to younger players in his approach. He understands what it means to be a United player and has embraced everything about this great club."
United begin their 2019-20 league campaign with a clash against Mata's former club Chelsea on Aug. 11.
(Reporting by Shrivathsa Sridhar in Bengaluru; Editing by Toby Davis)
