George Mason's Athletics director, Tom O'Connor, has confirmed that Larranaga is headed south to Miami.
He also says the Patriots will move "as quickly as possible" in their search for a new coach.
Larranaga spent 14 seasons at George Mason, where he became the school and the Colonial Athletic Association's all-time wins leader.
He led the Patriots to five NCAA tournament appearances, including a run to the Final Four in 2006.
Last season, Larranaga led George Mason to the Colonial regular-season title and an at-large berth in the Big Dance.
O'Connor says ultimately George Mason couldn't financially compete with what Miami was offering Larranaga.