The 22-year-old is coming to the end of his third season on loan at Atletico Madrid, who he has helped to win the Primera Division title and reach this season's Champions League final.
The Belgian international has admitted that he is unsure over his future with Chelsea.
Cech has made 479 appearances for the Premier League side since joining from Rennes in 2004.
However, Blues boss Jose Mourinho has told Courtois that he will be the first-choice goalkeeper at Stamford Bridge next term, according to Cadena Cope.
Courtois moved to Chelsea from Genk in June 2011.