Rainn Wilson lives in Los Angeles with his wife, fiction writer Holiday Reinhorn (Big Cats), and his son, Walter Mckenzie Wilson who was born in 2004. He grew up in Seattle, Washington but graduated High School from New Trier H.S. in Winnetka, Illinois. After attending both Tufts U. and the University of Washington, Rainn studied acting at NYU's graduate acting program and spent years doing theater both On and Off-Broadway, on tours (the Acting Company) and in the regions (The Guthrie, Arena Stage).

Rainn co-created and directed The New Bozena, a sketch comedy and post-modern clown show which performed in New York and ended up doing a pilot presentation at Fox TV. He made his directorial debut with a short film based on the show.

After many years of working in TV and Film, he became best known for playing Arthur, the odd love interest to Francis Conroy on Six Feet Under. His favorite role, however, is Bill Harris in the film, Gettin' the Man's Foot Outta Your Baadasssss!.

Rainn is a member of the Baha'i Faith.