A press officer from the New York Police Department told the Huffington Post website that the department had responded to a call at 10.05am at the address, where they found a 49-year-old woman unconscious and unresponsive.
They do not suspect foul play, and are treating it as a suicide. However, a medical examiner is yet to determine the cause of death.
One of the first to pay her respects was Mick Jagger's ex-wife, 68-year-old actress Bianca Jagger, who posted: "Heartbroken to learn of the loss of the lovely and talented L'Wren Scott. My thoughts and prayers are with her family. May she rest in peace."
L'Wren Scott: Career in pictures
Show all 20
Marc Jacobs, the former Creative Director of Louis Vuitton and current head designer for his own eponymous and diffusion lines, posted the following on Twitter:
"L'Wren Scott had a very clear notion of style which informed everything she did," Vogue editor Alexandra Shulman said. "It's not easy making the transition from stylist to designer, but every year L'Wren's recognition as a designer and creator of a brand was increasing."
Actress Olivia Munn posted: "Shocked and saddened by the passing of @lwrenscott ... she was an amazing soul, talented artist and an unbelievably giving friend. RIP." Similarly, Shameless actress Emmy Rossum tweeted: "So sad to hear of the death of L'Wren Scott. What a beautiful woman and an incredible designer."
Scott entered her career in fashion as a stylist, launching her own line in 2006.
Famous fans of her range included Oprah Winfrey, Nicole Kidman and Michelle Obama. Rumour had it she was set to design the wedding dress for Angelina Jolie for her forthcoming nuptials with Brad Pitt.
Scott was forced to cancel a recently scheduled London Fashion Week show following production delays.
Join our commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies
Join our commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies