The Adam Smith Institute's millionaire tracker estimates there were 442,000 millionaires in Britain last year, down 7% since 2024 and the lowest level since 2008 when there were about 400,000.
Drivers of the decline
The think tank attributed the drop to falling real asset prices, a low household savings rate, and the emigration of high-net-worth individuals. One in six people and families featured on The Sunday Times Rich List two years ago did not appear on the 2026 rankings, with researchers noting more British billionaires relocating to regions such as Dubai and Monaco.
Political reaction
Andrew Griffith, Shadow Secretary of State for Business and Trade, said: "Whatever their personal finances, everyone should care about Britain having fewer millionaires to contribute to the tax pot and creating jobs and businesses here. It's a competitive world, and when young and ambitious people are voting with their feet and leaving your country, that's a shameful sign."
Robert Jenrick, Reform UK's Treasury spokesman, said: "Labour's policies are driving successful people away from Britain, as this latest report from the ASI shows. Each millionaire that leaves means less money for the NHS or defence, higher taxes for working people, and fewer good jobs. We can't build an economy on envy."
Calls for policy change
Campaigners have urged the government to make the UK more attractive for high-net-worth individuals by abolishing inheritance tax, phasing out capital gains tax, and reforming the non-doms tax regime. Mitchell Palmer, economist at the Adam Smith Institute, said: "The decline in millionaires may be greeted as a success by some on the Left, but it should instead be viewed as a warning signal. Every millionaire that leaves means less capital for British businesses, fewer international connections, and weaker entrepreneurial spirit in the economy."
Palmer added: "Recently mooted anti-wealth proposals, such as a wealth tax or equalising the capital gains tax rate with income tax, will only make this problem worse. Instead, the Government should focus on making Britain an attractive place for ambitious people to build and keep their wealth. This includes cutting or abolishing inheritance tax and capital gains tax."
