Foxsports are reporting that the Phoenix midfielder, who is off-contract at season's end, is "on his way" to the Wanderers.
Bonevacia starred in Wellington's upset win over Melbourne Victory, bagging a double to keep their slim finals hopes alive.
In the minutes prior to Sunday's crucial clash, commentator Simon Hill revealed that the 25-year-old was set to join Tony Popovic's side.
"We understand that Roly Bonevacia is reportedly on his way to the Wanderers," Hill said.
The signing is a major boost for the Wanderers, who have a host of players coming off-contract including captain Dimas Delgado, Mitch Nichols and Terry Antonis.