The 19-year-old joined the Spanish club at the start of the season having never featured to the Blues.
With Petr Cech in front of him in the pecking order at Stamford Bridge, Courtois believes that another year in the Spanish capital would benefit his career.
"There is still time to decide on a second year or not," said the Belgian. "I like Madrid and Atletico Madrid, a very good club where I have made many friends.
"Playing here a second year would be good."
Courtois joined Chelsea in 2011 from Genk.