The 22-year-old German global has been a target for a number of European clubs, with his contract with Schalke set to expire.
Whether it's Borussia Dortmund, Hoffenheim, Bayer Leverkusen, Schalke or anyone else in the Bundesliga it's an nearly inevitability that if a player is player really well, especially a German one, they will end up at Bayern Munich.
Goretzka has scored four goals in 11 appearances for Schalke in the Bundesliga this season.
"Leon Goretzka informed us at the start of the week that he wants to leave the club and will join FC Bayern", said Schalke sporting director Christian Heidel.
He said: "We have noted this, with regret".
"He has signed a contract with Bayern from the 1st July 2018".
Speaking to Bayern's official website, Rummenigge said: "We are very happy that Leon Goretzka, a German worldwide who is a great prospect, has decided on FC Bayern, despite considerable competition from overseas". We did everything we could to try and keep him. We reached an agreement with him and his agent last summer.
Coach Domenico Tedesco added: "We are sad and disappointed to lose Leon as a player and character, but we have to accept the decision". There is no question that Leon is a fundamental part of this squad.
Schalke go into the 19th round of fixtures in third place in the Bundesliga, a point behind RB Leipzig, with automatic qualification to next season's Champions League a clear target.