McAvoy was born in Glasgow, Scotland, the son of Elizabeth (née Johnstone), a psychiatric nurse, and James McAvoy, a builder. McAvoy's parents divorced when he was seven, and he subsequently lived with his maternal grandparents, Mary and James Johnstone, in the Drumchapel area of Glasgow. His mother lived with them intermittently but McAvoy has not been in contact with his father since childhood. Read more...

McAvoy's first roles were in David Hayman's The Near Room in 1995 and then as Anthony Balfour in Pat Barker's Regeneration in 1997. He received his first big break was a role in the Steven Spielberg-produced miniseries Band of Brothers. His first international starring role was as Leto Atreides II in the 2003 Sci Fi Channel miniseries Frank Herbert's Children of Dune (adapted from Frank Herbert's Read more...

McAvoy previously dated Scottish actress Emma Neilson (stage name Emma King); they began dating when he was 16 and broke up in 2003. He married actress Anne-Marie Duff in 2006. They live in Stroud Green, London. He enjoys science fiction and is a fan of Celtic Football Club. He considers himself a spiritual person but no longer practices Catholicism.