Tamzin's character Mel had a turbulent love life
Tamzin's character Mel Owen is believed to be leaving the show in spectacular style.
But the actress will be staying with the BBC and is in covert talks about future projects .
The 30-year-old has played the part of Mel for three years.
New challenges
Her character has been involved in some of the most dramatic scenes in the recent episodes.
"I'll always be indebted to EastEnders for providing me with a wonderful start to my career on television and the opportunity to play a character like Mel has been fabulous," she said on Friday.
"I felt it was time to move on and try on a new coat - new characters, new challenges."
She is due to star in the BBC's upcoming film Red Cap.
"I've been treated impeccably by the BBC and would like to thank them as well all my friends at EastEnders especially my on-screen partner Martin Kemp," she added.
Tamzin's character Mel married Steve Owen, played by Martin Kemp, but the marriage proved turbulent.
'Most-loved characters'
Taken hostage by Dan Sullivan in recent episodes she discovered her husband was a cheat and got her own back.
She walked out on him, after setting fire to his infamous nightclub.
EastEnders executive producer John Yorke said: "Tamzin has created one of the most-loved characters and (with Martin Kemp) one half of the most-admired on-screen couple in EastEnders since the show started.
"She has been fantastic to work with and we wish her all the luck in her career."
But Mr Yorke did not rule out the actress returning to the soap.
"No doubt she may take on the mantle of Mel in the future as we'd welcome her return at any time," he added.