Olivia Palermo and Johannes Huebl reportedly picked up their marriage licence on Tuesday.
The couple are one step closer to tying the knot after being issued the necessary legal document at the Office of City Clerk Marriage Bureau in Manhattan, New York City, according to the New York Daily News newspaper.
The pair, who have been dating since 2008, got engaged on New Year's Eve after Johannes, 27, popped the question to the fashion designer, 28, while they were holidaying on the Caribbean island of St. Bart's.
The German-born model took to his Instagram account shortly after the romantic proposal to announce the happy news.
He uploaded a video of his stunning wife-to-be walking through luscious foliage before she is seen twirling around a palm tree to reveal her engagement ring.
In a message accompanying the clip, he wrote: "Happy New Year to everybody and this is how we celebrate it: OP said Y E S"
Johannes has previously told how he and Olivia have an "old romantic" approach to their relationship.
He said: "I think that I'm constantly learning, and we're both eager to learn about not only each other, but our interests. I think we have a very conservative, old romantic, private approach to our love."
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