She made her acting debut when she was 11, appearing in a single episode of Cracker ("The Big Crunch"). She then made appearances in Children`s Ward, Heartbeat, Doctors, and the children`s series, Life Force. Her big break came in 2000, when she beat Suzanne Shaw and Kimberley Walsh to the role of Maria Sutherland in Coronation Street. She and Jennie McAlpine also recently participated in a celebrity edition of Who Wants to Be a Millionaire?; they won £50,000 for charity.

Her film debut was a role of Sara in There`s Only One Jimmy Grimble. Smith was placed 52nd in the 2003 FHM`s 100 Sexiest Women in the World, and voted sexiest female by the readers of Inside Soap magazine in 2005. In the same year she impersonated Holly Valance in a celebrity version of Stars In Their Eyes- Which she won`. She also appeared alongside her Coronation Street castmates in a celebrity version of the TV show Family Fortunes in December 2006.

She married Matthew Smith, a property developer, on 10 September 2005 after a seven month engagement. She has also pledged her future to the ITV soap[5] and confirmed that she finds her sex symbol status weird in an interview with The Mirror. Samia went to the same school as her late on-screen husband Rob James-Collier.