"Mike Leach has established, and continued, a culture of success at Washington State, both academically and athletically, that few have matched," Washington State athletic director Pat Chun said in a release. "He has returned WSU to national prominence, is one of the top football coaches in the nation, and we are fortunate to have him leading our program."
The Cougars will make a bowl appearance for a school-record fifth consecutive season.
Leach has amassed a 55-46 record over his eight years at Washington State. He led the Cougars to a 6-6 record this season, with Anthony Gordon's nation-leading 5,228 passing yards powering the team.
Leach will earn $4 million per season.