The 22-year-old only joined Everton from Malaga during the summer, but he has made just three Premier League starts and 13 appearances across all competitions for the club since his arrival.
The Toffees revealed earlier today that they had reached an agreement with Sevilla over an initial loan move for the Spaniard, and the La Liga outfit have now confirmed that he has passed his medical at the club.
"Sandro Ramírez passed his medical this morning and has now signed his contract with Sevilla FC, after an initial deal for his loan was agreed this Tuesday between Sevilla and Everton. The Canary Island-native striker will travel to Leganés this today to meet his new teammates," read a statement on the club's official website.
Sandro could make his debut for Sevilla during Saturday's La Liga clash with Eibar.