Kristo Käärmann

Once a month for about a year, Kristo Käärmann and Taavet Hinrikus looked up the mid-market exchange rate and paid each other directly: euros into Käärmann's Estonian account, pounds into Hinrikus's London one. Neither man paid a bank a spread, and the favor they were doing each other became Wise.¹

Käärmann is the co-founder and chief executive of Wise plc, formerly TransferWise, a cross-border payments company listed on the London Stock Exchange. Wise lets individuals and businesses send, spend, and hold money across roughly forty or more currencies at the real, mid-market exchange rate rather than the marked-up rates and hidden fees that banks have traditionally charged.² It now also supplies that infrastructure to banks and partners through a service called Wise Platform.

Background

Käärmann is Estonian, and some profiles also report British citizenship given his long residence in London, though sources vary on his exact citizenship status. He has been reported as 45 years old as of July 2026, implying a birth year of roughly 1980 or 1981; his exact birth date and birthplace within Estonia are not confirmed in available sources. He holds a master's degree in computer engineering from the University of Tartu, a technical rather than a finance background. His upbringing and schooling before university are not documented in the sources reviewed.

Before founding the company, Käärmann worked as a management consultant at Deloitte in London.¹ Forbes has estimated his net worth at about $2.3 billion as of July 2026, and the UK Sunday Times Rich List put it at roughly £1.134 billion in 2023.³

Getting started

The company grew out of a problem Käärmann encountered in his own finances. In London around 2010 and 2011, he earned in British pounds but held a mortgage denominated in euros back in Estonia. He reconnected with Taavet Hinrikus, who had been the first employee at Skype and faced the mirror-image problem: Hinrikus was paid in euros through Skype in Estonia but lived and spent in pounds in London.

The two devised a manual fix. Each month they checked the mid-market exchange rate and swapped money directly: Hinrikus deposited euros into Käärmann's Estonian account, and Käärmann topped up Hinrikus's UK account with pounds. Each got the currency he needed without bank fees or a marked-up rate. They ran the arrangement as an informal personal favor for roughly a year before deciding to build it into a product.

In January 2011 they founded TransferWise to scale that peer-matching idea for anyone facing the same problem, aiming to avoid the roughly 5 percent fee, often concealed inside the exchange rate, that banks charged on international transfers.²

What he built

TransferWise launched in 2011 and moved about 10 million euros in its first year. Early press recognition followed in 2012, including mentions from The Guardian, Wired UK, and TechCrunch. Seed funding of roughly $1.3 million included PayPal co-founder Max Levchin. In 2013 the company raised a $6 million Series A led by Peter Thiel's Valar Ventures, and in 2015 a $58 million Series C backed by Andreessen Horowitz. Richard Branson was also an early investor.

The company reached profitability in 2017, six years after founding, and around that period customers were sending more than £1 billion a month.¹ A 2017 Series E of $280 million pushed its valuation past $1.1 billion, giving it unicorn status. Secondary share sales followed: $292 million in 2019 at a $3.5 billion valuation, and $319 million in 2020 at a $5 billion valuation.

On February 22, 2021, the company rebranded from TransferWise to Wise. On July 7, 2021, it went public through a direct listing on the London Stock Exchange, skipping the traditional underwritten IPO process, at a valuation of about $11 billion, roughly double its private valuation a year earlier and one of the largest UK technology listings of that era. Käärmann and Hinrikus were widely reported afterward as Estonia's first two billionaires.¹

By 2024 the company reported operations in more than 160 countries, annual revenue of about £1.0 billion, and roughly 5,500 employees.³

How he operates

Investors and press describe the founding mechanism itself as the core of Käärmann's method: identifying a system he personally experienced as broken, then replicating the fix at scale rather than inventing something abstract. The pattern is a fixation on a concrete, self-experienced problem, systematized into infrastructure. His edge is often characterized as an engineering one, built around a mid-market currency-matching engine, rather than a marketing one, consistent with his computer-engineering training.³

No independently verified direct quotes from Käärmann were available in the sources reviewed for this entry.

Where things stand

As of 2026, Käärmann remains co-founder and chief executive of Wise, which continues to trade on the London Stock Exchange. The company has drawn regulatory scrutiny on the same category of issue it was founded to address: in February 2025, the US Consumer Financial Protection Bureau ordered Wise to pay a $2.5 million penalty over allegedly inaccurate fee advertising and exchange-rate disclosure practices.

Käärmann has also faced a personal tax controversy. He was named on a UK tax authorities' list of deliberate defaulters in connection with a failure to pay roughly £720,000 in tax for the 2017 to 2018 year. The matter surfaced publicly in mid-2022 and raised governance questions given his role as chief executive of a regulated fintech, though he retained his position.

Key facts

• Käärmann and Taavet Hinrikus ran their currency swap as an informal personal favor for about a year, exchanging salaries by hand at the mid-market rate, before incorporating TransferWise in January 2011.
• Wise's July 2021 direct listing valued the company at about $11 billion, up from a $5 billion valuation the prior year, and made Käärmann and Hinrikus widely reported as Estonia's first billionaires.
• Early backers included Peter Thiel's Valar Ventures, Max Levchin, and Richard Branson.
• He was fined over a deliberate default on roughly £720,000 of personal UK tax for 2017 to 2018, disclosed publicly in 2022.
• He holds a master's in computer engineering from the University of Tartu, a technical background feeding a company whose edge is largely infrastructural.
• In February 2025, the US CFPB imposed a $2.5 million penalty on Wise over fee-advertising and exchange-rate disclosure practices.