The number of millionaires in the UK has fallen faster than in any other country, as rising taxation and changes to non-domiciled status prompt high-net-worth individuals to move their money, and often their residency, abroad.
According to new analysis by property consultancy Astons, based on data from the UBS Global Wealth Report 2025, the UK’s millionaire population declined by 14.3 per cent in the past year. While the country still accounts for 4.4 per cent of the world’s millionaires — around 2.6 million individuals — the fall represents the steepest annual decline of any nation.
By comparison, millionaire numbers grew significantly in emerging markets. Mexico saw a 20.3 per cent rise, followed by Brazil at 13.8 per cent and Russia at 11.6 per cent. Only five other countries – Australia, Japan, Saudi Arabia, Taiwan and Germany – recorded any drop at all.
Globally, the United States, China, France, Japan and Germany continue to dominate the rankings, together accounting for more than 64 per cent of the world’s millionaires. The US alone represents nearly 40 per cent of global wealth holders.
Astons attributes the UK’s sharp decline to what it calls the Labour government’s more aggressive taxation stance, particularly targeting non-domiciled residents. The tightening of tax rules on overseas income, capital gains, and inheritance has led many wealthy individuals to explore alternative jurisdictions offering more favourable regimes.
Suzanna Uzakova, senior consultant for residency and citizenship programmes at Astons, said the data reflected a clear shift in global wealth mobility.
“The significant decline in the number of UK millionaires is indicative of a broader trend where high-net-worth individuals are seeking more favourable tax environments,” she said. “Recent UK tax reforms have prompted many to reconsider their residency. Wealth is increasingly mobile, and countries like Greece offer structured and appealing alternatives.”
Astons highlighted Greece as one of Europe’s most attractive destinations for relocating investors, thanks to its Golden Visa programme. The initiative allows foreign nationals to gain residency – and Schengen Area access – in return for property investment.
Under revised Greek legislation, investors can qualify with a minimum €250,000 investment for properties converted from commercial to residential use, regardless of location. This lower threshold has reignited interest among investors priced out of other European schemes.
“The Greek Golden Visa offers one of the most accessible and stable routes to European residency,” Uzakova added. “It combines a competitive investment entry point with lifestyle advantages such as a high quality of life, strong property market and access to the wider EU.”
Astons’ findings underscore how wealth migration is reshaping investment flows. With the UK facing both political and fiscal uncertainty, southern European nations — led by Greece, Portugal and Spain — are emerging as the next investment hotspots for globally mobile millionaires.
