Kelly MacDonald was born in Glasgow, Scotland on February 23, 1976. After her parents divorced, she and her brother David were raised by their mother in Newton Mearns. As a child, she joined an amateur dramatics club one night every week for seven weeks.
She left her home when she was 17 and lived with a friend in a flat in Glasgow. She entered a college course on modern studies but dropped out. It was during her job as a barmaid when she was cast with Ewan McGregor in the movie Trainspotting which eventually became a huge international hit. Another film which gained her critical acclaim in Great Britain was her role as Stella in Stella Does Tricks. Although she had always planned on entering drama school, she moved to London instead and appeared in a string of movies.
She has worked with several famous names in the industry including Daniel Craig in Some Voices, Robert Altman in Gosford Park, Colin Farrell and Cillian Murphy in Intermission, Johnny Depp in Finding Neverland, and in 2007, the Coen Brothers, Tommy Lee Jones, and Javier Bardem in No Country For Old Men. She has also gained critical acclaim and award nominations in UK and in the international scene.