The 21-year-old has been the subject of intense transfer speculation after another impressive La Liga campaign at the Vicente Calderon Stadium in 2012/13.
Atletico Madrid owner Miguel Angel Gil Marin has flown to London to hold showdown talks with Chelsea about bringing the Belgian international back to the Spanish capital again next year.
Courtois arrived at Stamford Bridge from Racing Genk in 2011, but is yet to feature for the current Europa League champions.
And, with Petr Cech still performing well in goal for Chelsea, the youngster is unlikely to dislodge the long-term custodian in west London any time soon.
If Courtois wants to carry on playing regular football, he might be forced to look for another temporary move elsewhere.
Diego Simeone values Courtois as an integral member of his first-team squad at Atletico Madrid, so it would make sense for Chelsea to allow the player to continue his development at a club he is already familiar with.
The only potential hiccup in the prospective deal is if Blues owners feel it would be more beneficial for the goalkeeper to gain experience of playing in the Premier League, in which case they would look to loan him out to a domestic rival next season.