The mother-of-five showed off her brand new 'do on today's ITV's Loose Women, swapping her previously blonde locks for a bang-on-trend silvery purple hue.
A wig or permanent?
Well, she revealed half-way through the show it was a wig, quipping: "Why not have fun? Wait and see what I have for next week!"
It was certainly a different look to the one Katie, 37, sported on Monday's Loose Women, where she wore her hair in a very '80s-esque style of big blonde curls.
She had teased a change, saying today: "Ooh new hair colour for @loosewomen."
She's not the first celebrity to try out lilac locks. Just this week, Christina Aguilera debuted purple hair, while Kylie Jenner, Kelly Osbourne, Bella Thorne, Jessie J, Alesha Dixon and Caroline Flack have all experimented with the shade.
Katie is a total hair chameleon and never afraid to try new styles or colours. Long or short. Dark, blonde. Straight, curls. You name it, Katie has probably tried it!
She was joined on today's show by 13-year-old son Harvey, to talk about the online bullying he has faced. It's a subject close to her heart as earlier this year she named and shamed trolls who had posted offensive comments online about her first-born.
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