The Hilton hotels heiress wed billionaire James Rothschild (both 31 in lavish style in London on Friday and no expense was spared for the big day.
In addition to holding their reception at Kensington Palace's The Orangery, Nicky opted for a long sleeve lace dress, which bore a striking similarity to the Duchess of Cambridge.
Her couture Valentino gown cost an estimated €70,000, a steal in comparison to Kate's €350,000 Sarah Burton dress when she wed Prince William in 2011.
Before exchanging vows in the royal setting, the fashion designer said she always dreamed of a Valentino designed gown on her wedding day, telling Harper's Bazaar she was taking a hands on approach with the process.
"Ever since I was a little girl I wanted Valentino to design my wedding dress. Valentino is the definition of timeless elegance, I don't think there's another couture house like it," she said.
"I went through every look from their collections over the last 10 years," she added. "I studied the archives, and I just sent notes about details I liked - a certain sleeve, a high neckline."
In addition to her breathtaking 10 foot train, she topped off her look with a pair of white heels by Christian Louboutin with "Mrs. Rothschild".
Her sister, DJ Paris Hilton, who was also maid of honour, shared some behind the scenes snaps on Instagram.