Joined by her bestie, model and presenter Zara Martin, Millie made her way to two events in one night on Friday (5 September).
Which means the girls totally needed an outfit change, of course!
Given that the weather in New York is proper balmy right now, Millie opted for a cute off-the-shoulder dress with a floral print for the first event at NY's Lincoln Centre.
Teaming it with a pair of tan boots and a some sunglasses, we think she looks super fresh in this floaty number from Reformation.
Meanwhile Zara also opted for a dress from the US brand, going for a black halter neck which she matched with black boots and dark shades.
After partying it up at the bash, the girls decided it was high time to make their way to another event.
Stopping for a quick change, Zara and Millie ditched the florals and Millie went monochrome with a black skirt and tailored white top.
Zara rocked a sixties vibe with her metallic dress.
We love that both girls kept their outfits in tune all night long… Zara's monochrome clutch looks beaut with Millie's outfit here!
Posting a series of snaps of the night on her Instagram, Millie said: "Second outfit of the evening #standard #NYFW @zaramartin."
She and Zara flew to America on Thursday (4 September) and they hardly left themselves time to drop their bags off before they were in the swing of things!
In fact, Millie was so excited about their adventures that she took a selfie of the girls on their flight and has been keeping us updated with their trip ever since.
Looking good ladies!
Do you and your mates coordinate outfits before a night out like Millie and Zara? Tell us below, as the best comment from across the website each week wins £50!
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