The singer will be seen paying a visit to the Rovers Return pub in comedy scenes written for ITV's annual fundraiser, which will aid six chosen charities.
Cole's sketch sees her arrive in Weatherfield looking for Keegan's character Tina McIntyre. The Rovers barmaid is revealed to be one of Cheryl's childhood friends.
While Cheryl is expecting to be travelling home to Newcastle with Tina for her mum's Christmas party, not everything goes according to plan.
Speaking of her visit to The Rovers, Cole commented: "Coronation Street has always been part of my life - we'd all watch it as kids every night. It's surreal to be part of something I've watched my whole life.
"It's great to be able to support six wonderful charities and I really hope that this year's appeal makes a difference to many lives."
Steve McDonald (Simon Gregson), Michelle Connor (Kym Marsh) and Kirk Sutherland (Andy Whyment) will also feature in the sketch.
Text Santa will air on ITV at 8pm on Friday, December 20, with highlights including an exclusive performance by Robbie Williams. Other musical guests will be announced shortly.
As previously announced, the Pogues' Shane MacGowan has also filmed a separate Corrie sketch for Text Santa.
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