The 27-year-old has spent his entire senior career to date with the Bavarian giants, racking up exactly 400 appearances for the club in that time.
United were keen to lure the Germany international to Old Trafford in 2015 when ex-Bayern boss Louis van Gaal was at the helm, tabling an offer rumoured to be worth around £80m.
Muller opted to stay in the Bundesliga back then, though he is refusing to rule out an exit should fresh interest be shown further down the line.
"There was a stage when the subject arose two years ago when I considered it, but then the club immediately backed me and I was told I belong here," he told Kicker. "I didn't have to think about it a great deal after Bayern said we are counting on you and that you are an important man for us.
"Could I leave? Of course, it's possible. When my time is up, it's up. [Bastian] Schweinsteiger was here for over 10 years and now he's been gone for over two years and another player is here instead. It will be exactly the same with me. If I drop dead tomorrow, there will be a funeral, yet on Friday, 11 players will still be out on the pitch. That's life.
"At the moment, I don't think it's going to happen because I am very happy here. However, I'm not saying that somewhere different in the world definitely wouldn't be my thing either. If life takes you somewhere else then I would make myself at home there as well. I would follow the same principle as here, enjoying as many good things as possible every day."
Muller's landmark 400th appearance for Bayern at the weekend came nine years and 23 days after his first outing for the club.