Born Emma Thompson, her parents Colin and Gill Thompson trained at the Central School of Speech and Drama, and run an amateur dramatics society in Monmouth. Raised in Much Birch and wanting to act from aged three, aged 12 she took the lead role of Oliver Twist in Monmouth Comprehensive School's production of Oliver! At Hereford Sixth Form College she continued her acting career by taking on the role of Cherry Barnum in their production of "Barnum."
In the week after graduating herself from the Central School of Speech and Drama in London, she took the name Emma Stansfield under Equity rules (as actress Emma Thompson had already registered the name), and landed a role in the teenage play "Sparkleshark." Stansfield guest starred in the television series Holby City and The Royal, and then made her West End Theatre debut in Andrew Lloyd Webber's production of "Daisy Pulls It Off."
In 2007 she played a prostitute in the BBC's adaptation of Fanny Hill, and in April 2008 she portrayed Elaine Yates, wife of Jess Yates and mother of Paula Yates, in the BBC "Curse of Comedy" series episode, Hughie Green, Most Sincerely.
In 2008 she starred in the Irish drama Whistleblower as an English nurse called Louise.