KickOff.com first broke the news back in June that Hotto had chosen a move to Pirates, and the club officially confirmed the news on Monday.
"Choosing Pirates for me was an easy decision. This is a club that always competes at the highest level and it is also a club which has a rich history.
"During my time here at the club my ambition is to continue adding to the rich history of this club. The story of Orlando Pirates is well documented and for players, we all want to be a part of generations of teams that were successful. My aim is to achieve that here with Pirates and I will not stop until I do."