The versatile midfielder joins on a season-long loan deal.
20 year-old Williams has been an important part of Everton's U23s side over the past few seasons, winning praise and plaudits in a successful team that he has also captained on multiple occasions.
He won the Premier League 2 trophy with the Blues last season and also made the first team bench for the first time away at Old Trafford, continuing to impress Ronald Koeman with his hard-working attitude which led to a further four places on the bench.
This interaction and involvement within the match day squad at Goodison Park has given Williams some significant development at a young age and he is renowned for being a midfield enforcer. His tough-tackling approach and desire to regain the ball stands out, as well as the fact he can dictate play with a range of passing.
His fine performances have gained international recognition with the England U20s side, where he made his debut against Canada.
Paul Heckingbottom has tracked Williams for a while and been to watch him play for the Everton U23s side on multiple occasions, being impressed with the youngster and determined to bring him to Oakwell.
The head coach said, “We have been looking at Joe for a while and have been to see him play a few times. We have had success in player recruitment from Everton in recent times so I have to thank them for continuing to trust us with that. Joe will be a different type of player to what we have at the Club, as he has all the attributes and ability to be considered an all-round midfielder. We’re looking forward to him getting going and it’s important for him to now get some games in the remaining friendlies we have.”