Coronation Street character Janice Battersby, played by Vicky Entwistle, is to be axed from the soap, along with Sunita Alahan, played by Shobna Gulati.
Screenwriters have not decided how the characters will leave the Street
And Jessie, played by Nailah Cumberbatch, will also leave but ITV has denied newcomer Nathan Harding, played by Ray Fearon, is to go.
Writers have yet to decide how the characters will exit Weatherfield, but they will not be killed off.
The door will be open for a possible return, said producer Tony Wood.
The decision to write out the characters was taken at a long-term story conference last week, chaired by Mr Wood.
'Run their course'
Vicky Entwistle joined the cast as loudmouth Janice eight years' ago and Shobna Gulati joined Coronation Street in 2001 as shop worker Sunita Parekh.
Mr Wood said: "Shobna and Vicky are superb actresses who have proved extremely popular during their time on the show.
"However it is the nature of soap that characters come and go and the writing team and I felt that these characters had run their course for the time being."
Actress Shobna Gulati said she was looking forward to a "great exit storyline" while Vicky Entwistle said: "I have made some good friends and even met my husband working on this show - who could ask for more?"
The news comes during a triumphant year for the ITV soap.
This month, Coronation Street was voted ITV's greatest show in a poll to mark the channel's 50th anniversary and was named best soap at the joint TV Quick and TV Choice Awards.
Other plotlines coming up include a temporary split between favourites Jack and Vera Duckworth, played by Bill Tarmey and Liz Dawn, and a guest appearance by rockers Status Quo.
An average of 11.6 million people tuned in to see the first of two episodes of Coronation Street featuring Shelley's wedding day on Monday.
The second part drew 10.5 million viewers, boosting the soap's ratings by more than a million compared with the same time last week.