The former skipper, who has made 240 senior appearances for Millwall, is hopeful of finalising something by the end of the month with Northampton Town and Colchester United thought to be the leading contenders to land the popular centre half.
Explaining his decision, Wise said "We’ve told Nethers that he won't be offered a new contract, and in recognition of his service to the club we wanted to give him the best possible chance to get himself fixed up."
In response, Nethercott has taken the decision like the true professional that he is.
"Obviously I'm sad that I won't be around much longer because I've enjoyed six good years at The Den," said the former Player of the Year. "But I've known that his was coming for a little while now, and I'm grateful to the chairman and Dennis that they've been upfront with me and given me the chance to get myself sorted out now rather than be lumped in with all the other players who are out of contract in the summer.
"I've had one or two offers already, but I want to see who else might be interested before I make my decision."