The actress, who joined the BBC One show as Honey Mitchell in September 2005, will now depart later this year. Her on-screen husband Perry Fenwick (Billy) has been told that his job is safe.
An insider told The Sun: "Emma's a lovely actress, but we've just come to the end of her storyline. Honey will go this summer."
Emma said: "I'm looking forward to going back to musical theatre."
Honey has been at the centre of a number of high-profile plots during her time on the soap, including giving birth to baby girl Janet, who has Down's Syndrome, in 2006.