Born in September 1985 in Bristol, Kimberley Nixon is a former member of the National Youth Theatre of Wales. She trained at the Royal Welsh College of Music and Drama in Cardiff, where even before graduation in 2007 she had secured an agent on the strength of her performance in a college production. Her acting career began almost immediately when she starred as the motherless Sophy Hutton in the BBC One costume drama series Cranford. In 2008, she had supporting roles in the films Wild Child and Angus, Thongs and Perfect Snogging, and made her stage debut as Griet in a tour and London run of an adaptation of Girl With A Pearl Earring. Since then she has appeared in many more plays and films.
In May 2010, Nixon was named one of the "55 faces of the future" by Nylon Magazine's Young Hollywood Issue.