Number of UK millionaires hits lowest level since 2008 financial crisis

The number of millionaires living in Britain has hit the lowest level since the financial crisis, new research suggests.

Analysis by think tank the Adam Smith Institute (ASI) shows high taxes and slowing house price growth are among a range of factors that have hit people’s wealth.

The latest records from its Millionaire Tracker show that there were 442,000 sterling millionaires in Britain last year, down by 7% since 2024.

This has been blamed on falling real asset prices, a low household savings rate and the emigration of high net-worth individuals (HNWIs) amid the abolition of non-dom status and fears of a wealth tax.

To reverse this trend, the ASI is calling on the government to make the tax environment more welcoming to wealth creators. In particular, they’ve suggested the abolition of inheritance tax, cuts to capital gains tax and an international competitiveness assessment on the UK’s tax and regulatory treatment of non-doms and HNWIs.

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.”

Why is the number of UK millionaires falling?

The ASI uses Office for National Statistics data to estimate the number of constant-price sterling millionaires.

Its definition of a constant-price sterling millionaire is an adult British resident who has at least £1 million in individual net worth, across all real and financial asset classes, including pensions and property, measured in constant 2025 prices.

The figure of 442,000 is the lowest level since the 2008 financial crisis .

A range of factors have pushed this figure down.

The ASI said: “Higher interest rates, as well as a lack of confidence in the British economy, have mechanically reduced the inflation-adjusted values of pension pots and high-end London property.

“Moreover, Britain’s low savings rate has reduced the pace at which households make themselves millionaires. Finally, and perhaps most concerningly, there has been a well-documented trend of high net-worth individuals either leaving Britain or no longer choosing to move here.”

Millionaires are leaving the country for a number of reasons, the ASI said, including the abolition of non-dom tax status, high levels of general taxation, and a hostile culture for wealth creators.

The think tank also warns that calls for a wealth tax are misguided.

It said: “France, Austria, and the Netherlands all abandoned theirs after seeing vast outflows of millionaires or other avoidance behaviour. Given Britain is already haemorrhaging wealth, we could only expect similar results here.

“Every millionaire that leaves is a loss to the country. Both foreign- and British-origin millionaires bring jobs, capital, connections, and ideas to this country, which can create substantial wealth for other Brits.”

The think tank argues that millionaires already pay a disproportionate share of tax, with the top 1% of earners paying 29.1% of income tax.

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.”

How can you protect your wealth?

Many wealthy people may be concerned about calls for a wealth tax or higher taxes.

Nouran Moustafa, practice principal at Roxton Wealth, said she is seeing more high-net-worth clients ask how they can protect or diversify wealth outside Britain, with some considering leaving.

She said: “Those worried about preserving wealth should avoid panic. They should review diversification, tax wrappers, pensions, liquidity and estate planning, while keeping their strategy flexible enough to withstand future policy changes.”

Paul Denley, chief executive at Oakham Wealth Management, added: “For those staying, the answer isn’t panic but planning: diversify globally, use every available tax allowance, review estate and succession planning, and avoid irreversible decisions based on short-term headlines. Wealth is usually lost gradually through poor decisions, not overnight.”