Ethan Galbraith announced his signing for Leyton Orient in an Instagram post. He agreed to a two-year contract.
Manchester United released seven players earlier this month, including Galbraith.
He spent last season on loan with Salford City, where he was a consistent starter throughout the season.
New club founded by Ethan Galbraith
Ethan Galbraith made one first-team appearance for Manchester United in 2019 against Astana.
He is a Northern Ireland international, although he needed to play regular football at the age of 22.
He will now play for Leyton Orient, who won promotion to League One last season after Salford failed to make the playoffs.
Galbraith will be in League One for the second time, having previously played on loan with Doncaster Rovers.
Richie Wellens, his manager at Leyton Orient, signed him on loan for Doncaster Rovers in 2021.
“From playing against Leyton Orient last season, I got a good feel for the side here, and the style of football,” Galbraith told the O’s website.
“I know how he likes to play and how he wants to get the most out of his players, so it was a great fit.”
Galbraith had been linked with a move to Newcastle United, where he would have been farmed out, via National World. Stoke, Derby, and Sunderland were also involved.