Any lower and that neckline may have exposed her knickers - eek!
The reality star proved that there isn't a single look she can't pull off when she stepped out at the bash in this traffic-stopping, plunging black jumpsuit that boasted skinny cigarette trousers and cool cape-like sleeves.
It was evident that Tiff had ditched her bra to don the daring ensemble, but we reckon a whole 'loada boob tape was involved to keep her tatas in place as - rather amazingly - she managed to avoid an awkward nip slip while posing up a storm for the paparazzi.
Tiffany - who was joined by sister Lucy Watson, Nicola Hughes and Chloe Lloyd to name but a few guests - teamed her eye-catching number with a pair of pointed black courts and she cemented her fashionista status with an oversized metallic clutch bag.
Of course, she looked to make-up artist Laura Louise for her gorgeous glowing skin, bronzed lids and nude lip and rocked her lob (long bob, duh!) in a poker-straight style as not to detract from her one-piece's eye-wateringly low neckline.
EHEM. Stop staring!
Talking of risqué, this isn't the only WOWZA outfit Tiffany has turned heads in, recently...
Earlier in the month, the stunner - loved up with beau Sam Thompson - made everyone stop and stare as she flashed her undies in a see-through top at the Faberge launch.
You can't knock her confidence! Go, Tiff!
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