The gorgeous Coronation Street co-stars switched on the Manchester Christmas Lights at the Town Hall in Albert Square in front of thousands of onlookers.
Catherine, who performed at the event, looked festive in a red sparkling Nadine Merabi dress.
She told fans it was "an honour" to be asked.
Kym, meanwhile, looked chic and cosy in a fake fur-lined coat, glittery top and black skinnies.
Before taking to the stage, Kym tweeted her 639,000 followers saying: "Super excited to be switching on the Christmas lights in Manchester tonight!! Proper chuffed to be asked!! Who's coming down??"
The next day, she updated her fans, adding: "Great time last night turning on MCR Christmas lights! Thanks for looking after us and for inviting me down @KEY103."
Kym had another reason to be smiling so broadly, too - personal trainer Matt Baker!
The actress took her new beau with her to the special event and it's clear the pair are pretty smitten.
They are thought to have been dating for a few months.
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