The 22-year-old Academy graduate departs Goodison without having played a senior game for the club after being deemed surplus to requirements by Marco Silva and Marcel Brands.
Everton are believed to have rejected a bid worth in the region of £1 million from Wigan for Williams over the weekend but a second bid lodged this week has been deemed acceptable.
It is believed Paul Cook’s side have beaten off competition from rival Championship and Bundesliga clubs for the youngster.
↩️ | Joe Williams has this evening completed a permanent move to @LaticsOfficial.— Everton (@Everton) July 31, 2019
Very best of luck, Joe!
The Liverpool-born player joined Everton at the age of seven and was included in the senior squad for the first time for a Europa League game against FK Krasnodar in November 2014 but never made it onto the pitch.
Loan spells as Barnsley and Bolton Wanderers in the last two seasons gave the midfielder a much-needed taste of competitive senior football and he returned to Finch Farm this summer hoping to impress Silva and earn a place in his senior squad.
He scored a fine free-kick in Everton’s first friendly of the summer against Kenyan side Kariobangi Sharks playing in an advanced midfield role, but that was not enough to convince Silva to afford him a place in the senior squad for the coming season.
At 22, Williams needs to be playing regularly in order to continue his development and with just a year remaining on his Toffees contract it is a move that suits all parties. Williams is the second Everton youngster to leave for Wigan after full-back Antonee Robinson joined the Lancashire club earlier this month.
Former Everton player and manager Joe Royle is Director of Football at the Latics so his influence is likely to have played a part in the deal.
Good luck, Joe!