The 23-year-old and the Catalan giants have reached an agreement that will see the defender stay at Camp Nou until June 2017.
The 23-year-old's current deal is due to expire at the end of the season but the Catalan giants said Wednesday that the defender will sign a new contract in the coming days that will have a buy-out clause of 25 million euros.
Bartra, who celebrated his birthday Wednesday, joined the club at age 11 and is a product of La Masia academy.
The defender has found regular first-team opportunities difficult to come by with Gerard Pique, Carles Puyol and Javier Mascherano all preferred to the Spain international.
However, the center back has made eight league starts this season under coach Gerardo Martino and recently stated to the club's official website that he feels like a more important part of the team.
Meanwhile, the club is also hoping to tie down fullback Martin Montoya, as his contract expires at the end of the season.