Heidi Zak Created ThirdLove to Help Women Find the Perfect-Fitting Bra

The intimates brand focuses on customer feedback to create comfortable, quality bras available in a wide range of sizes.

Heidi Zak / WWD/Getty Images

After years of wearing ill-fitting bras, Heidi Zak realized something needed to change. She was tired of shopping at stores where the brand didn’t resonate and the product didn’t fit. After one particularly frustrating mall outing, Zak went home and started researching online bra brands for the modern woman. When she realized one didn’t exist, she created it: her brand, ThirdLove, was founded in 2013.

Today, Zak serves as the brand’s cofounder and CEO, and has built an online intimates brand that offers bras, underwear, lingerie, sleepwear and activewear for women of all shapes and sizes. Comfort and quality are both key, whether customers are shopping for T-shirt bras, minimizer bras or nursing bras. And throughout the last decade plus in business, ThirdLove has donated over $50 million of product to women in need while also focusing on sustainability efforts.

ThirdLove’s commitment to diverse sizing is really what sets the brand apart, and has been a staple of the company’s offerings since the very beginning.

ThirdLove / Courtesy of ThirdLove

“We figured out through a lot of testing that a lot of women were in between traditional cups and we created half cups,” Zak tells SI Swimsuit. “And that was probably one of our most innovative product features. Today, we’re the only brand in the world that I know of that offers half cups ... We offer a broad range of sizes with over 60 bra sizes, which is at the very high end of the range and we’re always thinking about how we can continue to add to that. We’re really starting with size because if you don’t have expansive sizes, then you can’t service as many women. That was always really important, as well as obviously quality and comfort and specifically this idea of creating products that were beautiful and comfortable.”

In addition to offering in-between sizes, Zak understands the pain point of trying to find a bra that fits, which is why ThirdLove offers a virtual fitting room. Roughly eight out of 10 women wear the wrong bra size, and 20 million women to date have used the brand’s online fitting room.

“The vast majority of our customers have [used the online fitting room], and 70% of the time, we recommend a size that’s different than the one she’s wearing,” Zak says. “So we’ve always stood by this idea of we have more sizes, we have these unique sizes and we’re going to help you find the right one because shopping online, that’s the biggest hindrance to buying a bra. It’s hard to buy a bra in the store, it’s hard to buy a bra online. So how can we try to make that easier?”

One of ThirdLove’s newest offerings, the Zero Edge wireless push-up bra, is a result of community feedback, from customer reviews to wear tests, in which women shared their frustrations over push-up bras that just weren’t comfortable.

ThirdLove’s Zero Edge bra / Courtesy of ThirdLove

“Hearing these real stories inspired us to rethink every detail—from seamless edges that vanish under clothing to soft, all-day comfortable fabrics—creating solutions that truly address their needs,” Zak explains.

The most rewarding aspect of being at the helm of ThirdLove, Zak says, is hearing how the brand’s products have impacted women’s lives. Whether it’s feedback from a breast cancer survivor who found the perfect fit with ThirdLove or a postpartum mom feeling great again in a new bra, customer feedback is what keeps Zak going.

“Your mission is never really about your product or service,” Zak notes. “It’s about a feeling you’re giving someone. It’s about something that’s deeper usually, and that is really important to have.”

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