The actress's character Heather Trott will bow out from the BBC drama "in dramatic circumstances" in early 2012, The Mirror reports.
An EastEnders spokesperson told the newspaper: "We can confirm Cheryl Fergison will be leaving EastEnders when her contract comes to its natural conclusion next year."
It is currently unclear whether Heather will be killed off in her exit storyline or if the door will be left open for the future. However, EastEnders sources have promised a "fitting end" for the character.
"Heather's character has been hugely popular over the years, but the decision has been taken to cut her out of the show before viewers tire of her," one insider told the tabloid.
"Cheryl will leave when her contract comes to an end, but it's set to be a dramatic exit which will see the character go out with a real bang."
Heather was initially introduced to EastEnders in June 2007 as a guest, but she was later upgraded to a Walford regular.
Memorable moments for the character include her double act with Shirley Carter (Linda Henry) and the 'Who's The Daddy?' mystery surrounding her 2009 pregnancy.
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