It is the 23-year-old's seventh loan spell since 2013.
Now the United academy graduate is excited to test himself in League One with the Brewers.
O'Hara said: "I'm ready to step up to that next level and show that I'm more than capable of climbing the leagues and reaching, hopefully one day, the Premier League.
"I hope I can play regularly and put in top performances for Burton. If that's recognised, hopefully that will help me make the next step of becoming a full senior international."
Need a VPN? Or seeking to switch? Then support Tribal Football by clicking here to sign up with our official partners NordVPN. Not only will you receive the best VPN experience, but also great discounts by signing up via Tribal Football. Thanks for your support!