The 25-year-old’s young family remain in the Spanish capital following a previous loan spell at Real’s cross-city rivals Atletico.
Courtois told the Evening Standard: “I’m committed to Chelsea.
“I have a contract until next year and I will be here. I will do my best for it.
“Obviously there is no extension signed but I don't think now is the moment to do it. I think it is better to wait until the end of the season.
“All I can say is I'm committed to Chelsea and also committed for next year.”
Pressed further on whether he can assure Blues fans of his presence for 2018-19, Courtois added: “I have no other thing to say. It's easy when you have only one year remaining that other people might say something.
“I'm a bit annoyed by it because it's a talking point and it's a thing people went to dwell on.
“That's the most important thing and is what we have to do as a group and for myself as well.”
Chelsea saw another route to major silverware closed in midweek as they crashed out of the Champions League to Barcelona.
Courtois has accepted blame for a disappointing 3-0 defeat following an uncharacteristic error-strewn display, but he is looking for the Blues to bounce straight back in an FA Cup quarter-final clash with Leicester on Sunday.
He said: “It is important that doesn't happen again and it is what the manager [Antonio Conte] has said to us.
“We have to take the effort and commitment we showed against Barcelona into the match on Sunday. If we have that same level of commitment, we will win.
“I know Leicester are a difficult team to face, especially away from home. We will do our best to win.
“The FA Cup is a great competition. We lost in the final last year and we are hungry to go to Wembley again and do something amazing.”