The future of the NBC comedy was in doubt, though a recent episode hit a season peak of 4.75m viewers.
"[Season four will be about] coming out of [testing times] and moving onto the next chapter of their life," McHale told reporters at NBC's summer press event in Pasadena.
The actor - who plays the charismatic Jeff Winger - also suggested that a fourth season need not be the show's last.
"There's graduate school, post-graduate, teaching," he hinted. "We could slow down time."
McHale again addressed the controversy surrounding his co-star Chevy Chase, who called Community a "mediocre f**king sitcom" in a series of abusive voicemails left for series creator Dan Harmon.
"He says that every day, and we say, 'Well, it's not [Chase's 2004 film comedy] Karate Dog'," quipped the star.
"He obviously wasn't very happy. But he loves the cast, [so] my guess is he'll be back if we're back."
Community airs on Thursdays at 8/7c on NBC. In the UK, the series airs on Tuesdays at 10.30pm on Sony Entertainment Television.
> Community exec: 'Very good chance of fourth season'
Watch a trailer for Community below: