Back in January, Groupon acquired fashion retailer ideeli for $43 million in cash to extend its presence in fashion and apparel. Such offers had already been popular on Groupon, and the company pointed to research estimating the off-price fashion market to be around $40 billion.

“By adding ideeli to our family, we’re better suited to grab a bigger slice of this market as we continue to position Groupon as the place you start when you want to do or buy just about anything, anytime, anywhere,” a spokesperson for Groupon told us at the time.

“Groupon’s brand, reach and vision as an ecommerce destination make it a tremendous place to continue to grow our company,” said ideeli CEO Stefan Pepe.

Groupon just provided an update on that growth. According to the company, the site has become one of the fastest growing flash sale apparel sites in North America. Since the end of Q1, billings and active customers have each grown more than 15 percent. The number of branded sales, curated events, campaigns and products has increased more than 400 percent.

“In 2014, we’ve seen a great response from customers as we’ve significantly expanded our offers to deliver even more world-class brands at an incredible value,” said Lisa Kennedy, president of ideel. “As a result, we’re seeing more and more shoppers inspired by our curated selection of the latest trends in fashion coming to us through our website and mobile app to score huge savings.”

Since being acquired by Groupon, ideel has been expanding its offerings in women’s and men’s apparel, shoes and home decor.The leading categories of growth for ideel include: women’s ready-to-wear items such as dresses (both day and evening), sweaters, active and intimate apparel, accessories like designer handbags, sunglasses, watches and jewelry, shoes (especially boots) and men’s shirts and sweaters.

Image via ideeli