The 19-year-old, who left Bury at the end of last season, has signed a deal until the end of next campaign, with the option of an additional year based on appearances.
"I'm obviously very pleased. I was very surprised because one minute I'm signing for Bury and then suddenly I got a call off Willco (Barnsley goalkeeper coach Ian Willcock) saying they wanted to sign me so I'm very pleased about it," he told the club's official website.
"I think of Ian as a coach, but he's a good lad as well who you can get along with. The same is with Ben [Alnwick] and Steeley (Luke Steele), who are two very good goalkeepers.
"I'm here to get better, develop and get fitter. I'm going to get stronger and it can only help that I'm training with better players and coaches who will get the best out of me."
A number of Football League clubs had also been monitoring proceedings.