SEBASTIAN SIEMIATKOWSKI

Born in Stockholm in 1981 to Bosnian immigrant parents. His mother cleaned houses.

His father drove a taxi. Siemiatkowski studied at the Stockholm School of Economics, where he and two friends — Niklas Adalberth and Victor Jacobsson — pitched "let people buy now and pay later online" at an entrepreneurship competition.

They lost. The judges thought it was a terrible idea.

He built Klarna anyway. Founded in 2005, the company grew slowly across Scandinavia before hitting escape velocity in the mid-2010s as e-commerce exploded globally.

By 2021, Klarna was processing $80 billion in transactions annually across 45 countries with 150 million users.

Then came 2022. Rising interest rates destroyed the economics of buy-now-pay-later.

Klarna raised at $6.7 billion — down 85% from $46 billion. It was the most public humiliation in European fintech history.

Siemiatkowski responded by cutting 10% of staff, replacing hundreds of customer service agents with AI, and turning the company profitable. Klarna filed for its US IPO in late 2024.

Co-founded Klarna in 2005. Grew it from a three-person Stockholm startup to a global payments company with 150+ million users across 45 countries.

Klarna partners with 500,000+ merchants and offers buy-now-pay-later, direct payments, and a full shopping app. Under his watch, Klarna became one of the first major companies to publicly use AI to replace human customer service agents — their AI assistant handled two-thirds of all service chats within a month of launch.

Siemiatkowski is a builder, not a public markets investor. His wealth is almost entirely tied to his Klarna stake.

His approach to business mirrors growth investing with extreme conviction — bet everything on one idea, scale globally, worry about profitability later. He is deeply influenced by the Amazon playbook: grow fast, dominate the category, and let margins come when you own the market.

Building Klarna from a rejected pitch competition entry into Europe's most valuable fintech startup. At its 2021 peak, Klarna was worth $46 billion — more than Deutsche Bank.

Even after the crash, the recovery to profitability and a US IPO filing proved the model works.

The 2022 down-round. Klarna raised at $6.7 billion after being worth $46 billion just a year earlier — an 85% drop.

The company had expanded too aggressively, credit losses spiked, and the zero-interest-rate environment that made BNPL economics work evaporated overnight. Siemiatkowski admitted they hired too fast and burned too much cash.

Growth at all costs — until the market stops paying for growth, then pivot to profitability overnight. Siemiatkowski proved he can play both games.

He has publicly said the BNPL model is not about lending — it is about owning the checkout experience. Whether you believe that distinction matters is up to you, but it has been worth billions.

Married with three children. Parents emigrated from Bosnia to Sweden before the war.

His mother worked as a cleaner and his father drove a taxi — a background he references frequently when discussing financial inclusion. "I grew up knowing what it's like to not have money.

That's why I built a product for people who need to manage their money carefully."

Stockholm School of Economics (BSc in Economics). The same school where he pitched Klarna and was told it would not work.

He has since been invited back as a guest speaker, which is the most satisfying possible revenge.

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