Allison Mack was born in Germany, but her family relocated to Long Beach, California, when she was just two years old. She began her acting career at the tender age of four, landing print work and commercial gigs, and subsequently enrolled in The Young Actors Space in Los Angeles when she was seven.
Before joining the cast of the popular television series Smallville in 2001, Allison starred in the short-lived Fox television comedy Opposite Sex in 2000. Prior to that, she was a regular cast member on the sitcom Hiller and Diller, working alongside renowned talents such as Richard Lewis, Kevin Nealon, and Eugene Levy.
Allison has also made guest appearances in several notable television shows, including the WB family drama 7th Heaven, where she portrayed a teenager struggling with the "cutting" trend in 1996.
In addition to her television work, Allison has starred in numerous made-for-television movies, including the cable film My Horrible Year! in 2001, directed by Eric Stoltz and featuring Karen Allen, Mimi Rogers, and Stoltz himself. She has also appeared in A Private Matter in 1992 alongside Sissy Spacek and Aidan Quinn, Living a Lie in 1991 with Peter Coyote and Jill Eikenberry, Unlikely Angel in 1996 with Dolly Parton and Roddy McDowall, and Stolen Memories: Secrets from the Rose Garden in 1996 starring Mary Tyler Moore and Linda Lavin.
As an accomplished dancer and singer, Allison currently resides in Los Angeles and enjoys reading, going to movies and plays, and spending time with her friends and family.