The firm, which specialises in research of ultra high-net-worth individuals, found the total wealth of the 20 wealthiest in the UK exceeded $27bn (£17.2bn)
Nine out of 20 people listed, five in the top 10, were born outside the UK and made up 66 per cent of the total wealth.
Top of the list was Chelsea FC owner Roman Abramovich who was born in Russia and is worth $12.1bn (£7.6bn). In second place was David Reuben, co-founder of private equity firm Reuben Brothers, who was born in India and is worth $4.8bn (£3bn).
Other names in the top 10 included William Fisher who was born in America and is worth $1.8bn (£1.1bn), Russian born Alexander Knaster and Michael Hintze from China.
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Mr Fisher is founder of London-based private equity firm Manzanita Capital and Mr Hintze is worth $1.4bn (£890m) from his hedge fund CQS. Mr Knaster is also worth $1.4bn from the sale of his stake in oil venture TNK-BP and is also founder of private equity firm Pamplona Capital Management.
The firm suggested the UK's non-domicile policy meant UHNWIs were choosing to spend more time in the UK.
This policy allows someone to be deemed a UK resident if they spend 183 days in a tax year or 90 days on average over four years in the UK.
Wealth-X chief executive Mykolas Rambus, said: "The high number of foreign born financers stands out on this list. This presents professionals in the banking, non-profit and luxury sectors with vast opportunities to engage these ultra-wealthy individuals."

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