Kate will play Jen Glover, an old-school rocker and no-nonsense music agent.
Kate said: "I am so excited to be joining EastEnders as Jen, we had a ball filming the scenes. It was surreal to be sat in The Queen Vic for my first scenes with some of the legends of Albert Square. Working alongside the team was a dream and I can't wait to see the scenes on screen."
A source told the Sun on Sunday: "Everyone was very excited to get Kate on board for this part, because they felt she was the perfect fit. Not only is she a great actress, but she has plenty of experience of the music industry too. And they weren’t disappointed — she did a brilliant job."
Kate's scenes will air next month. EastEnders continues on BBC One and iPlayer.