The former Alabama assistant's original deal with the Owls, signed before the 2017 season, was a five-year pact.
Though terms were not officially disclosed, Mark Heim of AL.com reports that Kiffin's annual salary will remain the same at $950,000, but the incentive-laden contract gives him opportunities to earn a number of bonuses.
"We are extremely excited about the contract extension," FAU vice president and director of athletics Brian White said. "Obviously, this came about because of the success that Lane (Kiffin) has had here. It shows Lane's commitment to FAU."
In Kiffin's first year as Owls head coach, he led the team to an 11-3 record and its first Conference USA Championship.