Helen Cotterill has had a long acting career since the early 1960s with one of her first acting roles being in the H.V. Kershaw-produced series for Granada, The Villains in 1964. The year after, she appeared in The Brain Drain, the final episode of the first season of the Coronation Street spin-off Pardon the Expression as Beryl, a vacuous shop assistant at Dobson and Hawkes who didn't even know the name of the then-Prime Minister, Harold Wilson. Twenty years later, she appeared in the video The Jubilee Years as Alice Hughes who had supposedly once lived at 13 Coronation Street before emigrating to Australia. It took until 2013 for her to appear in the parent programme as Margaret Cropper, Roy's stepmother. She appeared in the BBC soap The Newcomers in the late 1960s and also acted in popular dramas and comedies such as The Wednesday Play, Armchair Theatre, The Liver Birds, Love Thy Neighbour and had a regular role in the Thames Television comic-drama Born and Bred in 1980.

Her most recent credits include Casualty, Holby City and Doctors. Her extensive list of stage work includes three years with Sir Ian McKellen's Actors' Company on British, South American and Scandinavian tours and she is an accomplished watercolour painter and sells at exhibitions and by commission.