Move over, Pilates princess. Hailey Bieber is reigning supreme when it comes to post-workout fashion.

While she frequently opts for well-known brands like Alo and Fila, Bieber has recently been spotted in sporty-chic attire from Form, a lesser-known label created by wellness influencers and businesswomen Sami Clarke and Sami Spalter.

“Hailey is genuinely our inspiration, and we design with her in mind, so seeing her in our clothes is a dream come true,” Spalter shared with Page Six Style in an exclusive interview. She added, “There’s no greater satisfaction than witnessing someone feel comfortable and confident in Form’s creations.”

Last month, in a TikTok video, the beauty mogul showcased the brand’s Fitted Zip-Up Jacket, a stylish and lightweight option ideal for the mild Los Angeles winter.

Bieber’s expansive wardrobe also features the Scoop Tank and Criss Cross Bra, which she has donned on various occasions following her gym sessions earlier this year.

“Being an LA-based brand, we work closely with stylists and creatives, so you never know where Form might show up next,” Clarke tells us, when asked how Bieber found the brand.

“Those unexpected moments are our favorite because they feel so genuine.”

The Rhode founder’s not just a fan of Form’s sweat-ready styles, either; she’s also worn loungewear looks like the Boat Neck Long Sleeve, Fold Over Shorts and Sweater Halter — the latter of which she sported in a series of Instagram snaps with Kendall Jenner over the summer. (Jenner’s a Form fan, too, having been spotted in the brand’s cherry red Core Leggings in 2025.)

“These pieces support movement but also fit seamlessly into your day, whether you’re working out, traveling, or slowing down,” Clarke adds, noting that the label has “always been about more than just activewear.”

After all, while everyone from Rita Ora to Emily Ratajkowski has also worn Form over the years, the founders’ vision goes well beyond big names.

“We’re honestly proud any time we see Form worn in real life,” says Spalter. “These moments remind us that what we’re building resonates, and that’s always been the goal.”

This article was written by Hannah Southwick, Commerce Associate Editor for Page Six. Hannah spies deals on actually affordable celebrity-worn styles, puts celebrities’ brands to the test and finds the beauty products that keep stars red carpet-ready. She consults stylists and industry pros — including celebs themselves — for firsthand product recommendations, trend predictions and more. In addition to writing for Page Six since 2020, her work has been featured in USA Today and Parade.