The 28-year-old agreed an 18-month switch after failing to make an impact since arriving at San Siro from Porto in the 2012 close-season.
And, with one eye on the 2014 FIFA World Cup, Pereira is hoping he can hit the ground running at Morumbi, where his international captain Diego Lugano enjoyed a successful three-year stint before heading to Europe.
Former Uruguay internationals Pablo Forlan, Pedro Rocha and Dario Pereyra also sent time with the club, winning seven state titles and two Serie A crowns between them, with Pereira determined to emulate their achievements.
"It is a great pleasure and a huge challenge to play for Sao Paulo," he said. "I want to keep up the tradition of successful Uruguayan players here.
"It's a dream come true to play for one of the biggest clubs in the world."
Pereira had made just seven appearances in all competitions for Inter this season.
