Although the Bavarian club have yet to announce the deal, the Argentinian defender, who has suffered a tormented season after falling out of favour, told the Bild newspaper that the paperwork has been signed and he is heading for pastures new.
"I said my goodbyes to my team mates in the dressing room," the 30-year-old revealed.
"The transfer is completed. It has been seven unforgettable years."
Demichelis arrived in Munich in 2003 and, despite taking a while to make the breakthrough into the first team, his partnership with Lucio during the 2007/08 season helped set a new league record of only 21 goals conceded all season.
However, Bayern coach Louis van Gaal told him in the summer that he would no longer be considering him for the first team.
Demichelis did play a handful of games this season, but only when there was a severe emergency with players injured and suspended, and even then only after midfielder Anatoly Tymoschuk was unavailable to cover.
He made a total of 174 Bundesliga appearances.
