Antonio Conte's men have enjoyed an impressive run of results since losing to Liverpool and Arsenal in September, winning seven straight games to rise above their title rivals Manchester City and Liverpool into first place.
Despite their enviable position, the Blues only lead Jurgen Klopp's Liverpool side and Pep Guardiola's City team by one point, and Courtois believes Chelsea must keep their minds focused on winning each game as it comes before they can really start to think about securing the top-flight title.
"It was the same at Atletico [Madrid], we knew we could win trophies. It's the same with Chelsea now but there are a lot of teams who can say that.
"Manchester United, Arsenal, Manchester City, Tottenham, Liverpool - a lot of teams have quality. Yes, we have a team that should be able to play for a trophy but it's a long season. Maybe in March we can say we are contenders."