His elder brother Raymond Berengar III of Provence ceded Cerdanya to him in 1168. On Raymond's death, his eldest brother, King Alfonso II, named Sancho count of Provence.
In 1185, Alfonso dispossessed Sancho in order to make peace with the House of Toulouse. Nonetheless, Sancho continued to maintain the title of count of Roussillon. In 1209, his nephew King Peter II named him governor of Provence and lord of Languedoc. He was a regent for the young King James I.
Sometime before 1184, Sancho married Ermesinda of Rocabertí, daughter of Jofré of Rocabertí and Ermesinda de Vilademuls. In 1185, he married Sancha Núñez de Lara. By her he had one son, Nuño.