The TOWIE babe cut an elegant figure in a gorgeous white frock while posing for photographers at the bash, which was held at the Old Truman Brewery in London.
Lauren ditched the bodycon dresses in favour of a flowing gown complete with a plunging neckline, floaty skirt and a demure below-the-knee hem, plus a sash to help nip in her waist.
The stylista accessorised with silver jewellery and a nude glossy manicure while topping her pins with an adorable pair of T-bar pink high heels.
And the clothing designer gave Rapunzel a run for her money with her long, tumbling locks, completing her look with bronze shimmery eyes, fluttery lashes and a dab of peachy lipgloss.
(If you fancy recreating her look, Lauren recently revealed her smoky eye must-haves - check them out here!)
The starlet has now finished filming series 12 of TOWIE, and the season finale ended happily ever after for Lauren as she and co-star Lewis Bloor finally made their romance official!
Viewers saw Lewis ask the pretty blonde whether she would like to be his girlfriend, to which she said yes before sealing the deal with a kiss - awww!
And, clearly smitten with her handsome new beau, Lauren took to Twitter during the episode to say: "How could a girl resist :) #towie."
We love those two already!
The new free to air channel truTV, the home of larger than life characters in real situations, will hit UK screens on the 4th August on Freeview channel 68, Sky channel 565 and FreeSat channel 154.
What do you think of Lauren's white dress? Let us know by commenting below as the best comment across the site each week wins £50!
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