Fundraising Fox

Sebastian Siemiatkowski

Founder

Co-founder & CEO at Klarna

Stockholm, Sweden

FoundedKlarna

Find your path to Sebastian

1 people in our graph share verified history with Sebastian — schools, employers, funds. One of them is your warm intro.

Photo, via Wikimedia Commons ↗

About

Sebastian Siemiatkowski's idea finished near the bottom of his business school's entrepreneurship competition in 2005. He built it anyway. Twenty years later Klarna serves more than 120 million consumers and a million merchants across 26 countries on $3.5 billion of annual revenue and $127.9 billion of volume, holds a full Swedish banking licence, and listed on the New York Stock Exchange in September 2025 at $40 a share — the largest NYSE listing of the year. He co-founded the company at 23 with two Stockholm School of Economics classmates, having worked out the problem while selling invoice factoring to small businesses; before that he was a telemarketer at 17 and, at 15, flipped burgers alongside his future co-founder Niklas Adalberth. The son of Polish immigrants to Uppsala, he has since run one of the most aggressive AI transformations of any public company and co-founded the listed investment vehicle Flat Capital with his wife Nina.

Beyond investing

Education
Read economics at the Stockholm School of Economics, starting Klarna at 23 while on sabbatical from his studies.
Family
Born in Uppsala in 1981 to Polish parents who emigrated to Sweden in 1980; he worked at Burger King at 15 and as a telemarketer at 17.
More
The three founders pitched the pay-after-delivery idea at their business school's 2005 entrepreneurship competition and placed near the bottom.

From published sources — common ground for a warm intro.

Co-founder & CEO at Klarna

Intro paths

In turn, Sebastian can intro founders to Klarna's investors below.

Co-founders at Klarna

VJ

Podcasts & interviews

featuring Sebastian Siemiatkowski

Klarna CEO Sebastian Siemiatkowski on Q3 results, state of the consumer and future of fintech

cnbc.com

Klarna CEO Sebastian Siemiatkowski on Their Blockbuster Comeback

Sourcery with Molly O'Shea

Klarna CEO Sebastian Siemiatkowski on the IPO, Loving Walmart, and Embracing AI | Fortune Term Sheet

Fortune Magazine

Watch CNBC's full interview with Klarna CEO Sebastian Siemiatkowski

cnbc.com

Klarna CEO Sebastian Siemiatkowski on Getting AI to Do the Work of 700 Customer Service Reps

Sequoia Capital

Sebastian Siemiatkowski (CEO, Klarna) on the Future of Klarna, Valuation Changes and AI in Finance

The Logan Bartlett Show

Frequently asked questions

Who is Sebastian Siemiatkowski?
Sebastian Siemiatkowski's idea finished near the bottom of his business school's entrepreneurship competition in 2005. He built it anyway. Twenty years later Klarna serves more than 120 million consumers and a million merchants across 26 countries on $3.5 billion of annual revenue and $127.9 billion of volume, holds a full Swedish banking licence, and listed on the New York Stock Exchange in September 2025 at $40 a share — the largest NYSE listing of the year. He co-founded the company at 23 with two Stockholm School of Economics classmates, having worked out the problem while selling invoice factoring to small businesses; before that he was a telemarketer at 17 and, at 15, flipped burgers alongside his future co-founder Niklas Adalberth. The son of Polish immigrants to Uppsala, he has since run one of the most aggressive AI transformations of any public company and co-founded the listed investment vehicle Flat Capital with his wife Nina.
Where does Sebastian Siemiatkowski work?
Sebastian Siemiatkowski is Co-founder & CEO of Klarna.
What companies did Sebastian Siemiatkowski found?
Sebastian Siemiatkowski founded Klarna.
What podcasts and interviews feature Sebastian Siemiatkowski?
Tracked appearances include "Klarna CEO Sebastian Siemiatkowski on Q3 results, state of the consumer and future of fintech", "Klarna CEO Sebastian Siemiatkowski on Their Blockbuster Comeback", "Klarna CEO Sebastian Siemiatkowski on the IPO, Loving Walmart, and Embracing AI | Fortune Term Sheet", and 3 more.