Hedge fund billionaire Chris Rokos has joined the ranks of ultra-wealthy residents leaving the UK, in a decision likely to cost the government billions of pounds in lost tax revenue.

Rokos, founder of the investment firm Rokos Capital Management and a taxpayer of more than £300m last year alone, is relocating from the UK to Greece. His move to Athens, first reported by Bloomberg, comes after the Mediterranean country introduced new rules allowing wealthy foreigners to pay a flat annual tax of around 100,000 euros — roughly £86,000 — on all overseas income. Greece is one of several European countries, including Italy and Switzerland, that have courted relocating wealth with preferential tax regimes for high-net-worth individuals, giving the departing UK rich a wider set of alternatives than in previous decades.

According to the Sunday Times Rich List's estimate of his last UK tax bill, the departure of the Eton and Oxford-educated investor means the Exchequer could miss out on some £330m each year. The same Sunday Times study found he paid the third most tax of any individual in the UK, and he has an estimated net worth of more than £2bn. Rokos made his name as a co-founder of macro hedge fund Brevan Howard before setting up his own firm, which trades across global markets.

Rokos joins a series of billionaires and centimillionaires who have left the UK in recent years after being targeted at consecutive Budgets. In 2025, City AM revealed that Goldman Sachs vice president Richard Gnodde left the UK in response to the government's crackdown on non-doms. Other wealthy investors to have ditched the UK include Aston Villa co-owner Nassef Sawiris, Checkout.com founder Guillaume Pousaz and steel tycoon Lakshmi Mittal.

Wealth exodus deepens

The Labour government, in power since 2024, has come under fire from top City investors over its stance on the rich, with tax rises blamed for driving a wealth exodus.

The government has ended the non-dom regime that allowed wealthy foreigners to avoid paying tax on income earned outside the UK, scrapped a VAT exemption on private schools, increased capital gains tax rates and announced a plan to impose a new levy on mansions. The abolition of the non-dom regime, which had existed in some form for more than two centuries, marked one of the most significant changes to the UK's treatment of internationally mobile wealth in decades.

Andy Burnham said in an interview that he wanted wealth creators to stay, although he has faced questions over his stance on taxing the rich. Chancellor John Healey also said he supported wealth creation in the UK in a speech on the UK economy on Monday.

Scores of Labour MPs have publicly endorsed a wealth tax, which would add a two per cent annual levy on assets valued at £10m. Tax experts and economists have warned that a wealth tax would deter investment and lead to lost revenue, with administration costs across Whitehall also racking up.

A more likely tax hike at the Budget could be on capital gains, as cabinet minister Wes Streeting said a higher levy would represent a "wealth tax that works".

Conservative Party campaigners have argued that a higher tax rate on capital gains — with the higher rate currently standing at 22 per cent — would actually lose the Treasury revenue, as investors would choose to sit on their assets until the rate came back down.

Record amounts of capital gains tax were recorded in the 2024/25 tax year, reaching £127bn, an 82 per cent increase from the prior year.

Simon French, chief economist at Panmure Liberum, said: "The dynamic, behavioural effects of policy are more significant with capital gains taxes than almost any other part of the tax system.

"The latest data pours cold water on the idea that there is a pot of recurring tax revenue to go for here."

Rokos Capital Management declined to comment. The Treasury was also approached for comment. With further Budget decisions looming, the scale of future departures — and the tax receipts they carry with them — is likely to remain a live point of contention between the government and the City.