The UK has seen the biggest fall in millionaire numbers of any nation, according to new research by international property consultancy Astons.
The analysis reveals that the UK’s millionaire population has dropped by 14.3% over the past year, a decline driven by major tax increases affecting high-net-worth individuals and significant reforms to the non-domiciled regime.
Astons’ study, based on the Global Wealth Report 2025, examined the annual change in millionaire numbers across global markets.
While the United States, China, France, Japan and Germany continue to hold the largest shares of the world’s millionaires, accounting for 39.7%, 10.5%, 4.8%, 4.6% and 4.5% respectively, the UK sits just outside the top five with 4.4% of the global total, equivalent to around 2.6 million individuals.
However, unlike countries such as Mexico, Brazil and Russia, where millionaire numbers have grown by 20.3%, 13.8% and 11.6%, the UK has experienced a steep decline.
Alongside the UK, only five other countries, Australia, Japan, Saudi Arabia, Taiwan and Germany, recorded reductions in their millionaire populations.
The UK’s fall was the most pronounced and was accompanied by a 3% decline in average personal wealth.
Astons attributes this downturn to recent fiscal policies, including adjustments to capital gains tax, inheritance tax, and the dismantling of long-standing non-dom arrangements.
These changes have prompted many wealthy individuals to leave the UK for jurisdictions with lower tax burdens, while others have seen their net worth eroded under the new system.
Residency-by-investment schemes, known as Golden Visa programmes, are becoming an increasingly popular option for those seeking to relocate.
Astons identified Greece as one of the most appealing destinations, citing its accessible investment thresholds, Schengen Area access, and favourable legal and tax frameworks.
Suzanna Uzakova, senior consultant for residency and citizenship programmes at Astons, said: “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.
“Recent UK tax reforms, such as changes to inheritance tax, capital gains tax, and the non-domiciled regime, have prompted many to reconsider their residency.
“Wealth is increasingly mobile, and countries like Greece offer structured and appealing alternatives.
“Greece’s Golden Visa programme remains one of Europe’s most attractive options, with a minimum investment of €250,000 required for properties converted from commercial to residential use.
“This threshold applies regardless of the property’s location, making it accessible even in high-demand areas.
“Additionally, the programme provides the benefit of Schengen Area access, a stable legal framework, and a high quality of life, all of which contribute to its growing popularity among relocating investors.”
