The actress, who announced her decision to leave the show earlier this year, shot her final scenes as Becky McDonald today (December 9).
Kelly took to Twitter this morning to tell fans: "Last day filming on the cobbles..."
She returned to the microblogging site in the evening to announce: "It is done. Becky has left the Street! I hope you enjoy the departure Corrie viewers. Final eps on screen Mid Jan. Enjoy! It's all for you x"
Fellow Corrie star Paula Lane, who plays Becky's half-sister Kylie Platt, expressed her sadness at Kelly's departure from the soap.
"Filming some very emotional scenes today with my on screen big sis @katherine_kelly," she tweeted. "Everyone is gonna miss her so much :-("
Earlier this week, details were revealed of an emotional scene outside a hotel between Becky and Steve (Simon Gregson), which forms part of the final chapter in the ongoing love triangle between the two characters and Tracy Barlow (Kate Ford).
Becky is also rumoured to be involved in dramatic scenes in this year's Christmas Day episode.
Speaking of her choice to leave the show, Kelly previously said: "It's been one of the hardest decisions of my life.
"I love Coronation Street and everyone here. I have had the most blissful five years, I wouldn't change one moment of it - but it feels like the time is right to say goodbye to Becky."
> Coronation Street films emotional Steve, Becky scenes: In Pictures
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