Chris Smalling has signed a new contract with Manchester United that runs until at least 2022.
The 29-year-old defender, who joined the club from Fulham in 2010, was due to be out of contract at the end of the season.
A club statement said the deal included an option to extend for a further year.
Smalling said on manutd.com: “This is my ninth season with the club and I am delighted to be continuing my progression with this team.
“It is a real honour to play for Manchester United and we are all now concentrating on the busy schedule of games throughout the festive period.”
Jose Mourinho has often seemed unsure of his first-choice defence but Smalling has been the one near-constant, failing to start only five games this season.
He has made more than 300 appearances for United in all competitions and should start against Liverpool on Sunday assuming he has overcome a minor foot problem.
Mourinho said: “I am very happy Chris has signed a new contract. Chris has been with the club for a number of years and is now one of the senior players within our squad.”