Wealth Taxation Wiki
A wealth tax is a recurrent levy on an individual's net assets, defined as the total market value of owned assets minus liabilities.[^c1] Unlike a property tax, which is limited to real estate, a broad-based net wealth tax applies to most or all types of assets, including financial securities, business equity, cash, and personal property. As of 2025, only three European countries—Norway, Spain, and Switzerland—along with Colombia outside Europe, maintain such broad-based net wealth taxes. France replaced its broad wealth tax with a real estate-only levy in 2018, and several other countries tax selected asset classes without imposing a true net wealth tax.
The modern debate over wealth taxation has been substantially shaped by the work of Thomas Piketty and Gabriel Zucman, who argue that the tendency of returns on capital to exceed economic growth generates increasing wealth concentration that progressive taxation must counter.[^c2] Piketty's Capital in the Twenty-First Century made the case for a progressive annual tax on capital, arguing that existing tax systems fail to capture the economic capacity of the wealthiest individuals during their lifetimes. Zucman has since developed proposals for an internationally coordinated minimum tax on billionaires, which gained consideration at the G20 level and was debated in the French parliament.
The historical record of wealth taxes is one of widespread adoption followed by gradual repeal. The number of OECD countries with net wealth taxes peaked at twelve in the mid-1990s and then declined steadily as countries cited low revenue yields, high administrative costs, capital flight, and valuation difficulties as reasons for abolition.[^c3][^c4] Among countries that retained their wealth taxes, revenue ranges from 0.21 percent of GDP in Spain to 1.19 percent in Switzerland. Proponents of wealth taxes argue that previous failures were due to design flaws—excessive exemptions, poor enforcement, and lack of international coordination—rather than inherent defects in the concept. They point to evidence that global billionaires face effective tax rates as low as 0 to 0.5 percent of their wealth, and that a modest 2 percent minimum tax could raise $200 to $250 billion annually from fewer than 3,000 individuals worldwide.[^c5][^c6]
The central questions in wealth tax design involve trade-offs between breadth and administrability, rates and behavioral responses, national sovereignty and international coordination, and the balance between taxing wealth stocks and income flows. These questions intersect with fundamental debates about inequality, economic growth, property rights, and the role of the state in shaping the distribution of economic resources.