Spade was found dead inside her home in New York on Tuesday, US media reported.
One of the most well-known accessories designers in the world, Spade founded her namesake brand with her husband-to-be Andy Spade in 1993, pioneering a wave of bright and stylish clothing and accessories that catapulted her business to global prominence.
Spade is survived by her husband and their 13-year-old daughter.
While the Kate Spade business still bears its founders name Spade herself had not been involved with the business for some time, having sold the majority of the business to Neiman Marcus in 1999.
The business was acquired by Coach (Tapestry) for $2.4b in 2017, while Spade herself launched a new brand called Frances Valentine in 2016.
The New York Times and Associated Press reported that the death was an apparent suicide.
Despite not being involved the brand for some time, Spade’s design ethos was popular with some of America’s most prominent celebrities, who expressed an outpouring of support on social media overnight.
My grandmother gave me my first Kate Spade bag when I was in college. I still have it. Holding Kate’s family, friends and loved ones in my heart.
— Chelsea Clinton (@ChelseaClinton) 5 June 2018
Kate Spade (the business) took to social media on Tuesday (US time) to break the news to customers.
“Kate Spade, the visionary founder of our brand, has passed,” the business said.
“Our thoughts are with her family at this incredibly heartbreaking time.
“We honour all the beauty she brought into this world.”
Very saddened to hear about the passing of Kate Spade. Mental illness does not discriminate and can happen to anyone with any circumstances. I hope she has found peace ❤️ — Lucy Hale (@lucyhale) 5 June 2018
I am heartbroken about the news of Kate Spade. I have worn her clothes many, many times. They were colorful, bold, cheerful, and encouraged women to find the twinkly person inside them. You couldn’t walk into her boutiques and not smile. Rest In Peace, Kate.
— Mindy Kaling (@mindykaling) 5 June 2018
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