Both Pérez brothers are football fans, stating that they thought about leaving car racing to play professionally. The brothers are friends of Mexican international Javier Hernández. In an interview in 2012 for the official Formula One website, Pérez revealed that if he had not been a driver he would have liked to be a lawyer.
In November 2012, Pérez unveiled the Checo Pérez Foundation to support orphans and children with cancer. His sister Paola was the foundation's president. In December 2017, Pérez and his partner Carola Martínez welcomed their first child, Sergio Pérez Jr. Pérez and Martinez were married on 1 June 2018. On 14 September 2019, their second child, Carlota Pérez, was born.
On 28 September 2012, Lewis Hamilton's decision to leave McLaren for Mercedes in 2013 was announced, and Pérez was subsequently confirmed as Hamilton's replacement. He also replaced Hamilton in McLaren's cartoon Tooned. This also ended Pérez' association with Ferrari, as he was released from its driver academy.