Tom Dumont is the band's guitarist. He joined No Doubt after leaving his sister's heavy metal band, Rising, adding an edge to the band's ska sound.

Tom was born on January 11, 1968 in Los Angeles, California. He claims that he has three addictions: surfing, home decorating, and collecting old radios. His major in college was music. Tom says that his musical influences include Alex Lifeson of Rush and Ritchie Blackmore of Deep Purple.