Chuck Billy is an american singer, most known for being the lead vocalist of the thrash metal band Testament since 1986. Billy has remained constant as the vocalist alongside guitarist Eric Peterson who also was an all time permanent member. However, his vocal style has changed over the years from a clear thrash style to a death grunt. Since the Low album, he has mixed both styles and sometimes performs both on the same song.

Chuck has also appeared on the solo projects of James Murphy, playing on both albums as a guest musician. He also has sung lead vocals for Exodus at at least one concert recently (October 28, 2004 at the Warfield Theater in San Francisco, opening for Megadeth).

In 2006 Chuck Billy Did vocals on the Sadus «Crazy» and, along with several other musicians from other bands, did a cover of Iron Maiden’s «Fear of the Dark» for their Numbers from the Beast tribute album.

Chuck Billy has also hooked up with musicians such as Steve Souza, Greg Bustamante, Steve Robello, Andy Billy, Dan Cunningham & Willy Lange to form the band Dublin Death Patrol.

In 2001, Chuck Billy was diagnosed with germ cell seminoma; a rare kind of cancer in his case because it is usually in the testicular region of a man’s body, but he has it in the chest region near his heart. However, following chemotherapy, he has since been given a clean bill of health and continued his work with Testament. In August 2001, friends organized the Thrash of the Titans benefit concert, held to raise money for Chuck’s medical expenses.

Chuck Billy is of the Pomo Native Americans, an indigenous people of Northern California. He is proud of his American Indian heritage, sometimes giving a shoutout to his «Indian brothers and sisters» in the audience. The song «Trail of Tears» is a tribute to his heritage, as is «Allegiance».

His younger brother Eddie, was the original bassist for Vio-Lence. He also sang on a Tribute Version of Metallica’s «Seek and Destroy», alongside guitarist Jake E. Lee, drummer Aynsley Dunbar, and Bassist Jimmy Bain.