* Bill Miller (Mark Addy): The father of the Miller family, he is often perceived as an obese, lazy idiot. Bill has a tendency to partake in "macho" activities, such as watching sports, carpentry, and drinking beer. Although Bill is not the most intelligent person in the bunch, he still manages to be the family's main bread-winner, working at a Sears-like department store's toilet department.
* Judy Miller (Jami Gertz): The mother of the Miller family, she is a woman in her late 30s trying not to lose touch with her younger self while raising her kids. Judy works as a dental hygienist at a dentist's office. She is more intelligent than Bill (although that isn't saying too much).
* Brian Miller (Taylor Ball): The son and eldest child of the Miller family, Brian is a gifted senior in high school. Brian has a poor social life and is unpopular at school, because people see him as a geek, nerd, or dork. Brian's sexual orientation has been questioned several times by his parents, because he reads Vogue magazine (although he justifies this by saying that "sometimes those models wear see-through clothes, and it gets cold in those studios"), twirls a baton, and is a school cheerleader (which Brian later reveals as his way to meet cute girls). In addition to his unpopularity, in later seasons, he is ignored or even neglected by his parents.
* Lauren Miller (Renee Olstead): The older daughter of the Miller family, Lauren is one of the popular girls at school, and is attending her sophomore year. Lauren could be described as a typical teenage girl. She gets in trouble for breaking her parents' and the school's rules. She is smart, but doesn't apply herself as much as her brother Brian does.
* Tina Miller (Soleil Borda): The youngest child and daughter of the Miller family, Tina could be described as an obnoxious second grader. Tina's family see her as a clueless child, but viewers see that she is probably one of the most clever in her family.
* Linda Michaels (Jennifer Irwin): Judy's younger sister, Linda spends much of her time hanging around the Miller house, much to Bill's chagrin. She suffers from low self-esteem and seems to feel sorry for herself. She laters marries to Perry, a singer in a Foghat coverband.