Kristo Käärmann net worth | Evening Standard Tech Rich List

As a consultant living in London in 2019, Kristo Käärmann made what he called an “incredibly stupid” decision; he tried to send his Christmas bonus back home to Estonia.

Käärmann said the transfer cost him around £500 because of the interest rate used by the bank. So he struck a deal with fellow Estonian Taavet Hinrikus, who was paid in euros but needed pounds: they would send each other money instead of trying to change currency.

In 2011, the pair formed a company built on that workaround — Transferwise, which later became Wise.

Even after Wise made him a billionaire, Käärmann hasn’t been immune to costly personal finance blunders. He was fined £366,000 in 2021 after appearing on HMRC’s list of deliberate tax defaulters, which his spokesperson said was because he forgot to file his taxes.

In May, he announced he would take a three-month break from work to spend time with his newborn baby boy.

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