The 22-year-old defender had a three-month stint at the Bees, where he made 18 appearances and scored one goal.
Pearce will now attempt to break into County's first team but has not ruled out the possibility of returning to Underhill in the future.
"I have definitely enjoyed my time here and I am sad to see it come to an end," he told the Barnet Times. "It was always going to be for these three months though.
"I just want to be playing games, though, so if I go back to Notts County and I am not able to play then it is a definite possibility (of returning).
"It has been an experience that I can certainly learn from and take a lot from. It has been a good few months for me."
- Sports & Recreation