Bosom buddy: ThirdLove’s Heidi Zak is changing the way we buy bras

Thirdlove Bras

What was the first thing you did when you got home today? If you took off your bra the minute you walked through the door, then chances are you have yet to discover the joy of wearing ThirdLove — a San Francisco-based brand well on its way to joining Calvin Klein and Janet Reger in the line-up of Jewish lingerie greats.

Former Google executive Heidi Zak co-founded ThirdLove in 2013. Since then, this online-only lingerie brand has shaken up the industry with a truly inclusive range of sizes and colors. Bras come in sizes 30-48, with cups that range from AA-H, including their signature half cup sizes.

ThirdLove is famous for its game-changing Fit Finder® tool (used by over 12 million women); and, most recently, for a well-publicized spat with Victoria’s Secret. More importantly, Zak and designer Ra’el Cohen have created a modern, beautifully-fitting t-shirt bra that’s pretty close to perfect.

I talked recently with Zak about bras and more. Here’s what she had to say.

Making an impact

ThirdLove’s Heidi Zak and bra designer Ra’el Cohen

What has surprised you most since launching the brand?

What surprised me the most is actually how vocal women are about their bras. When we started we were like, “Oh well, people will never post on social media. They’ll never share. They’re never going to talk about their bras.” It’s been really interesting to see that… they do share. They’ll tell their friends; they’ll tell anyone who’ll listen.

Your size range is pretty inclusive already, but are you looking to widen it still further in the future?

So when we started I believe we had around 25 to 35 sizes, which is about the size range of your average bra brand. But yes, we’ve added so many sizes over the past few years. We’re currently at 74 and we’ll be at 78.

And what about the half sizes?

They’re about a quarter of our business. In the early days nobody believed us that half sizes were even something that was needed. For sure that’s been impactful.

What is the next technical/design challenge for you?

We haven’t done an unlined bra. All of our bras have some type of foam cup. And so that’s something that’s definitely on the list.

Lingerie for the everyday

Is there another brand or particular bra that makes you feel jealous that you didn’t invent it?

I obviously look to some of the higher end Parisian brands — Lou is a great example. And they’re so Parisian; they’re so beautiful. I mean, they’re just gorgeous. They’re also extremely expensive and totally not practical. But they definitely speak to me when I see them. What we do a lot of is, “How do we take pieces of that and make a bra that women will actually wear and buy because it’s not that expensive?” So I do appreciate that aesthetic that they have.

What do you think is the most common lingerie mistake that women make?

The most common mistake is they’re wearing the wrong size. We find with 70 percent of women who do Fit Finder, we recommend a different size than what she thinks she is. So that’s the biggest one. Generally speaking, women tend to be wearing a band that’s too large and a cup that’s too small. So a lot of women for example walk around thinking they’re a 34B where maybe they’re a 32C. They’re indexed to this larger band and that throws off the fit.

Reshaping an industry

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I loved your not-Victoria’s-Secret social content! [ThirdLove hosted an evening of “empowering conversation” on Instagram on the night that the Victoria’s Secret Fashion Show was screened]. Do you think that we are seeing a genuine change in the culture?

Victoria’s Secret continues to dominate the market, and I don’t think they have changed or seem to be changing anytime soon. That said, there are a lot of other players in the space who are joining in this movement for inclusivity and really making sure that people get it. But I think there’s still a lot more work to be done for sure.

What’s religion got to do with it?

Got to ask a Jewish question! Has Judaism influenced how you are building your business?

I converted actually, so I’m an interesting one because I went through the process when I was in my early 30s. What has always struck me as the connection to Judaism is the fact that there’s a lot about owning the relationship with the religion… meaning it’s on you to ask a lot of questions. Ask why, and make it into your own something that works for you personally and for your family. That’s something that really resonated with me, and when you think about how that applies to the company here, I think I also have expectations that people ask a lot of questions, own their own journey… And I think those are really important pieces of running a successful business as well.

This interview has been edited and condensed.

Susannah Cohen is a fashion journalist, e-commerce editor (specialist subjects: lingerie and diamonds) and Jewish mom. Recently relocated from London to the West Coast, she’s feeling a lot more spiritual these days.