The reality starlet looked a million dollars and more in the magenta Matthew Williamson maxi dress that featured a trailing hem, a classic high-neck detail and stunning blooms adorning both the skirt and the body.
Rosie trumped guests such as Tamara Ecclestone, Sinnita and even Hollywood superstar Lindsay Lohan in the style stakes as she came away with the best dressed crown.
According to the Reveal fashion desk, anyway...!
Rosie looked like she had strolled straight out of a fairytale in the billowing dress which she teamed with a snappy hot pink clutch bag that boasted a mock croc effect and she went all out when it came to her locks!
Rosie - who usually wears her hair down - opted for a charming, fuss-free up-do and we just adore her dishevelled halo braid!
She looked to the make-up maestros at Tom Ford for her sultry smokey eye and Kylie Jenner-esque matte nude lip - can we also get a round of applause for that pretty incred contour?
Rosie posed up a storm in her floaty frock at the city event before mingling with the rest of her sharply dressed celebrity pals. It's always a fashionable affair with her in attendance, right?
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