Saracens announced via their official website that Wilson will join the Sharks with immediate effect.
The 25-year-old arrived in London in December 2012 and has scored six tries in 19 appearances for Saracens.
Mark McCall, Saracens' Director of Rugby, commented: “Jack
has made an excellent impression, but he would like to return to the
southern hemisphere and seize this opportunity in South Africa. Our
policy is always to align the interests of the club with the interests
of the player, and we will not stand in his way.”
Wilson will join up with Saracens team-mate Mouritz Botha at the Sharks. South African-born Botha was signed by the Durban-based franchise earlier this month.