The Belgium international joined Real Madrid from Chelsea for £35m in the summer of 2018 and has made 130 appearances for Los Blancos, keeping 52 clean sheets.
Courtois has won one Spanish La Liga title, one Spanish Super Cup and one FIFA Club World Cup during his time at Real Madrid.
"Real Madrid and Thibaut Courtois have agreed to extend the player's contract for five more seasons, until June 30, 2026," read the club's statement.
The 29-year-old previously had a three-year spell at Real Madrid’s city rivals, Atletico, where he won the La Liga and Europa League while on loan from Chelsea.
He also won two Premier League titles, one FA Cup and one League Cup during his time with Chelsea.
Courtois was named the best goalkeeper at the 2018 FIFA World Cup in Russia, where Belgium finished in third place.
Courtois played in all Belgium’s games at EURO 2020 as the Red Devils reached the quarterfinals. He has won 89 caps for his country.
Courtois started Real Madrid’s first La Liga of the season on Saturday against Deportivo Alaves which resulted in a 4-1 win for Carlo Ancelotti’s men.
