The 22-year-old will reprise his role as Sam on the Fox series on a recurring basis starting with the third season's eighth episode, TV Line reports.
"We missed Chord and Chord missed us," a source told the website. "It's a win-win."
Overstreet was previously offered a recurring role on the series, but turned it down in order to pursue a career in music.
"They offered me the chance to come back for a few episodes, but there was nothing guaranteed so I decided to dive into the music thing," Overstreet said at the time.
The actor has been rumoured to be dating Emma Roberts since April.
Glee airs Wednesdays at 8/7c on Fox.
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