The 22-year-old is contracted to parent club Chelsea, but has spent the last three seasons at the Vicente Calderon, where he has developed into one of the best stoppers in world football.
After winning La Liga with the capital outfit on Saturday, Courtois suggested that he will return to England to continue his career.
"The day I leave Atletico, I will miss the fans the most. The love they've shown me has been immense," Inside Spanish Football quotes the Belgian as saying.
"Three years ago, I never could've imagined we'd be where we are. Now comes the Champions League and then the World Cup. We don't know what'll happen.
"My three years here have been incredible. Atletico will always be in my heart."
Barcelona have also been credited with an interest.