The Adam Smith Institute’s latest Millionaire Tracker, based on Office for National Statistics data, estimates that Britain now has 442,000 sterling millionaires, down 7% since 2024. The think tank defines a sterling millionaire as an adult UK resident with at least £1 million in net worth, including property, pensions and financial assets, measured in constant 2025 prices. Tax Policy in the SpotlightThe report links the decline partly to changes in UK tax policy, including the abolition of the non-dom regime, which ended in April 2025 after reforms that began under the previous Conservative government and were extended by Labour after it took office in 2024. Speculation about a possible UK wealth tax has also featured in the debate. Supporters of a UK wealth tax argue that those with the greatest financial resources should contribute proportionately more, particularly at a time of strained public finances.