Has three children with Amelia Warner: a daughter named Dulcie, born in Vancouver, British Columbia, Canada, on 21 November 2013; a second daughter, Elva, born in the UK on 16 February 2016, and a third daughter, born in the UK on 31 March 2019.
His father, Jim Dornan, was an obstetrician and gynecologist who, according to Jamie, has delivered over 6,000 babies in his lifetime. His father died on March 15 2021 from COVID-19.
Was in a relationship with actress Keira Knightley from 2003 to 2005. They met on the set of an Asprey photo shoot in 2003.