The starting senior defensive tackle had been awaiting word on an academic eligibility appeal to the NCAA, according to sources.
Farmer, a Tabor City, N.C. native, is the only returning starter along UNC’s defensive line.
"We're thankful to have Ethan cleared to play and I know he's excited to have this behind him," Larry Fedora said in a statement.
"Ethan is our only experienced player (and) we'll be counting on him for senior leadership in that group. He has practiced hard during the preseason and has not let this situation affect his preparation for the season."
Farmer started all 13 games in 2013, totaling 30 tackles, 2.5 tackles for loss and a forced fumble from his nose tackle position.
He practiced throughout training camp while awaiting news of the appeal.
“There isn’t a better person in the world than Ethan Farmer and I’m saddened that the situation is like it is for him,” associate head coach for defense Vic Koenning said earlier in fall camp. “I know he’s worked his complete tail off to get within one semester of graduating."
UNC suffered two academic casualties at nose tackle this preseason in senior Shawn Underwood and red-shirt freshman Greg Webb.
The Tar Heels open the 2014 season at Kenan Stadium on Saturday against Liberty.
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