Born Eileen O'Higgins on 22 January 1987 in Castlewellan, County Down, Northern Ireland, where she grew up.

O'Higgins later studied at the Royal Welsh College of Music & Drama in Cardiff.

She then appeared in theatre productions including Alice Birch's And Then There Were Four Little Beats of Four Little Hearts on the Edge of the World at The Old Vic.

[4][5] Her appearance helped her to be cast in a supporting role in her first film Brooklyn (2015) which also starred Saoirse Ronan.

[10] O’Higgins is best friends with fellow actress Saoirse Ronan,[11] whom she first met during the filming of Brooklyn in 2014.