Miller told ESPN after OSU beat Oregon 42-20 to win the College Football Playoff National Championship Presented by AT&T that he hasn't made a decision yet and that he doesn't know when he will make one.
Asked whether he would be at Ohio State next season, Miller added: "I've got to get my shoulder right."
Miller suffered a season-ending shoulder injury before the 2014 campaign started.
Ohio State coach Urban Meyer previously said he expects Miller to return next season.
Miller, after graduating, could transfer and play immediately at another school this fall if he desires.
J.T. Barrett, the redshirt freshman who replaced Miller before also suffering a season-ending injury, told SI.com on Monday night that he doesn't think there will be any movement.
"This is from somebody who is going to be in the competition, I don't believe anyone is going to transfer," Barrett told SI.com.
"I'm not leaving. I don't think Braxton is leaving. I don't think Cardale (Jones) is leaving. That's being honest. With that, I mean, it's just competition. It's part of football. It's what we're about to do."