The famous mum paired her jaw-dropping navy outfit with Prada heels, Stephen Webster jewellery, smokey metallic eyeshadow and wore her famous blonde tresses loose and immaculately wavey.
WATCH: Amanda Holden twirls in white beach dress
Amanda has certainly been bringing the heat with her BGT outfits in recent weeks, and we're still not over the eye-popping look the mother-of-two rocked on last week's show.
The star looked mesmerizing in a daring thigh-skimming custom mini dress by Jennifer Clair.
Amanda looked sensational on Saturday
The white frock featured silver embellishment, an elaborate Bardot neckline, and a risqué leg split.
Amanda's stylist Karl Willett shared a stunning photo of her on Instagram ahead of the third semi-final, and fans adored her stylish dress, with one writing: "Looking gorgeous as always."
Amanda also shared a preview of her frock on her Instagram Story, alongside a funny clip of herself dancing her way onto the stage.
Amanda wowed yet again last week
The week before that, Amanda wore a frock straight out of a fairytale, wowing audiences in a beautiful black and white dress by bridal designer Pronovias.
The dress featured a stunning black bodice that spilled out into a circular train.
But most spectacular of all were the frock's puffed white sleeves, which looked like clouds on either side of Amanda's shoulder.
We can't even begin to imagine what the fashionista will wear for the popular show's finale…
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