The actress has already filmed her final scenes as Amber Kalirai, who will exit Weatherfield next month.
Amber was most recently involved in a lesbian love triangle with Sophie Webster (Brooke Vincent) and Sian Powers (Sacha Parkinson).
"Nikki's part in the love triangle was a huge success, but the producers feel that the character has run her course. Nikki is a professional and she understands, although of course she is disappointed," a source told The People.
Amber will leave the Street after a series of rows with stepmum Sunita Alahan (Shobna Gulati).
A Coronation Street spokesperson added: "Nikki will be leaving us at the end of her contract, but viewers may see Amber again."
Vincent was recently offered a "mega-bucks" deal to stay at the soap.