She studied acting at Rose Bruford College in Sidcup. A well as her role as PC Hemmingway in the ITV series The Bill, she played the character Marsha Harris twice in 2001. Austin had roles in Mike Leigh's films Secrets & Lies (1996) and Another Year (2010). She also has a small role in ITV's 2008 teen drama Britannia High as Mrs Doris Troy, the landlady of the main characters, in the comedy Never Better and as a nurse in BBC's Outnumbered that aired on 30 August 2009.
In December 2010, she appeared in the British BBC soap opera EastEnders as Gloria MacDonald. On 12 February 2013 she played the part of Estelle in an episode of Death in Paradise on BBC1.