Both ladies have snapped up this prim and proper slim-fitting frock by Jason Wu, which features a crisp white collar and demure below-the-knee hemline (and retails at a whopping £945 - gulp!).
Chezza rocked the look while attending The X Factor press launch at the swanky Ham Yard Hotel yesterday (27 August), looking very pleased with her fashion choice as she posed for photographers.
The newlywed paired her frock with pointed monochrome heels and a bold red mani to match her rouge pout, finishing with an elegant updo and a bronzed glow.
But we bet she wasn't too chuffed to discover Katherine already sported the same dress in public, two months before!
The opera singer was spotted attending the Best of Britain's Creative Industries reception in London on 30 June.
Blonde bombshell Katherine added a touch more colour to her getup with electric blue toe-cap heels while leaving her locks to tumble past her shoulders, finishing with a pair of pearl earrings.
So... let the battle of the fashionistas commence! Who do you think wore their frock best?
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