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Heidi Zak

Co-Founder & Co-CEO

Co-Founder and Co-CEO of ThirdLove

Turned an unpleasant bra shopping experience into a revolution in the underwear industry. Passionate about making great-fitting, comfortable and beautiful bras for all women. Loves chasing her kids around San Francisco’s playgrounds and cooking for friends and family.

How to Measure Your Bra Size

March 12, 2020  |  Heidi Zak

Traditional bra sizes explained and how you can find your perfect fit.  80% of women are wearing the wrong bra size, but a lot of that has to do with the understanding of bra size and measurement remaining a mystery— which is completely unnecessary. We are leveraging our bra expertise to break this all down…

What Are the Best Bras?

March 06, 2020  |  Heidi Zak

The question our Co-Founder Heidi Zak asked herself as she started a bra revolution.  For Thirdlove, the company, the product, and the name, started with the idea that for too long, women were forced to choose between two options when it came to bras: over-the-top sexy, and unflattering modesty – neither one looked great.  And…

Our Co-Founders explain why they chose to sign a letter to the Senate demanding action to prevent gun violence.

September 12, 2019  |  Heidi Zak

Teammates – We are writing to tell you about a letter to the United States Senate that we signed along with the CEOs of roughly 145 other American companies, including Levi’s, Airbnb, Gap, Omnicom, Twitter, Pinterest, and many more. The letter was delivered to Capitol Hill early this morning and demands action to prevent gun…

Founder Friday: How to Contribute to Workplace Progress as a Female Entrepreneur, with Heidi Zak

March 07, 2019  |  Heidi Zak

As a #ByWomenForWomen company, we love celebrating brands that are led by fellow female founders. Our new series, Founder Friday, is a chance to get to know some of these standout women, including our very own Heidi Zak! Everyone needs a role model. We all need someone we can point to and aspire to be…

Founder Friday: How a Dating Mentality Helps Me Hire Star Employees, with Heidi Zak

February 08, 2019  |  Heidi Zak

As a #ByWomenForWomen company, we love celebrating brands that are led by fellow female founders. Our new series, Founder Friday, is a chance to get to know some of these standout women, including our very own Heidi Zak! Over 10,000 applications were submitted to ThirdLove last year, and I personally interviewed 130 people. At some…

78 Sizes. One Perfect Fit.

February 07, 2019  |  Heidi Zak

When I started ThirdLove, I set out to create a brand that all women could rely on. So with a promise like “Bras and underwear for every body” comes a responsibility to uphold it. It’s not an empty tagline that we preach because it sounds nice; it’s a way for us to hold ourselves accountable….

Founder Friday: How We Use Data at ThirdLove, with Heidi Zak

January 10, 2019  |  Heidi Zak

As a #ByWomenForWomen company, we love celebrating brands that are led by fellow female founders. Our new series, Founder Friday, is a chance to get to know some of these standout women, including our very own Heidi Zak! If there’s one thing I’ve learned from starting ThirdLove, it’s that I have to focus on solving…

Founder Friday: Looking Back on a Year of Growth at ThirdLove, with Heidi Zak

December 24, 2018  |  Heidi Zak

As a #ByWomenForWomen company, we love celebrating brands that are led by fellow female founders. Our new series, Founder Friday, is a chance to get to know some of these standout women, including our very own Heidi Zak! 2018 has been quite a year for ThirdLove. If you had asked me five years ago where…

Founder Friday: How I Manage My Business During the Holiday Season, with Heidi Zak

December 17, 2018  |  Heidi Zak

As a #ByWomenForWomen company, we love celebrating brands that are led by fellow female founders. Our new series, Founder Friday, is a chance to get to know some of these standout women, including our very own Heidi Zak! Many different labels can describe one person — a mom, a founder, a wife, a friend. But…

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