Flanagan first appeared as Rosie Webster in Coronation Street in January 2000. In 2006, she was nominated for the award of "Best Dramatic Performance from a Young Actor or Actress" at the British Soap Awards, losing to Ellis Hollins of Hollyoaks. In 2007, she was nominated for "Villain of the Year" at the same awards, this time losing to Coronation Street co-star Jack P. Shepherd. In 2010, Flanagan appeared in Coronation Street spin-off Coronation Street: A Knights Tale as her character Rosie Webster. Then in 2011, she had her own Coronation Street spin-off Just Rosie, which explored her character Rosie Webster trying to build a modelling career in London. In October 2011, Flanagan announced that she would leave Coronation Street in February 2012 to pursue other interests.