According to Sky Sports, the Anfield side will pay £20m across Thiago's four year contract, with the potential for £5m add-ons and the midfielder will wear the No 6 jersey.
Bayern Munich coach, Hansi Flick also confirmed the move when he revealed Thiago already said his goodbye to teammates and staff at Bayern.
"Thiago is an exceptional player who spent seven hugely successful years here. He is a wonderful person and an outstanding professional. It was very emotional when he said goodbye to us all."