The Online Bra Brand Betting Its First Store on Walnut Street
The retail space at 1611 Walnut Street has become something of a proving ground for direct-to-consumer brands.
Menswear label UNTUCKit was there first, then DTC bra brand ThirdLove, which decamped to King of Prussia Mall in late 2022. Now Underoutfit, which opened its first-ever brick-and-mortar store there on November 15, 2025, is betting it can make the address stick.
A ‘mini Fifth Avenue’
“When we came to look — and there weren’t that many vacancies, by the way — we looked at Rittenhouse Row and were like, ‘This is a mini Fifth Avenue in Philadelphia,’” said Steven Castellano, Underoutfit’s founder and chief product officer. “You have Alo Yoga across the street and an Apple store next door. There’s a lot of connectors to those brands.”
Founded in April 2020, Underoutfit sells wire-free bras it describes as so comfortable you’ll forget you’re wearing them, along with shapewear and underwear for women of all ages.
The brand grew quickly online, posting seven-figure growth in an 11-month stretch in 2021. But Castellano, a veteran of Victoria’s Secret and Maidenform, sees the physical store as something more than a retail outpost. He calls it a “lab.”
“Having conversations with women face to face is an amazing thing,” he told Fitler Focus. “There’s only so much information you can get out of people communicating through their computer.” The store lets his team gather direct customer feedback and use it to shape future designs — something no e-commerce dashboard can fully replicate.
Philadelphia was an easy call, Castellano said, after customer data showed Pennsylvania ranking among the brand’s top markets. The logic for Rittenhouse Row followed from there.
Why you really can’t shop for bras online
During my recent visit, I began to understand why intimate apparel in particular benefits from the in-store experience. Store manager Angelina DeCarlo measured my band and cup size in the dressing room before walking me through the wall displays: bralettes, clasp-back bras, shaping camisoles, and sports bras. Since Underoutfit uses its own size chart that diverges from standard bra sizing, her guidance was genuinely useful in finding the right fit.
DeCarlo, who previously worked at ThirdLove, said the fitting process is often what converts online skeptics into regulars. “She bought a few styles of bras online but ended up returning them for a different one that I showed her in the store,” she said of a recent customer.
Her clientele runs the gamut. “We get a lot of people who work in the area and are looking for a comfortable bra they can wear to work. Some come on their lunch breaks because they work around the corner. We also get a lot of older women who are retired and want something comfortable for their day-to-day.” She’s helped customers from their mid-20s into their 70s, each with different priorities around support, coverage, and fit.
From Rittenhouse, with an eye on expansion
DeCarlo said she’s bracing for a rush during Walnut Street’s next Open Streets event on April 6, after the last one brought in a wave of new shoppers. Meanwhile, Castellano is already looking ahead — he has his sights set on California and New York for Underoutfit’s next boutique locations.
From the Community
Thrilled to learn about this as the caretaker for an elder struggling to find the right fit!