North Melbourne confirmed on Monday morning that Wells had rejected their two-year offer and would join the Magpies on a three-year contract.
Wells is an unrestricted free agent, meaning Collingwood do not have to wait to see if North match their offer.
He is leaving Arden St after 14 seasons and 243 games.
AFL games record holder Brent Harvey, Drew Petrie, Michael Firrito and Nick Dal Santo all left North at the end of the season after the club did not offer them new deals.
“We’re obviously disappointed to be losing someone of Daniel’s calibre but we respect his decision,” North football manager Cameron Joyce said.
“Daniel has been an outstanding player and person and we wish him all the best.
“We have benefited from free agency over the past few seasons and fully respect the system.”
Dal Santo and Shaun Higgins have joined North under free agency.
Wells played 19 senior games this season, but injury restricted him to only two last year.
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