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Wealth & tax · UK-wide

The Green Party's wealth tax: who would pay, and how much?

An annual levy on the very largest fortunes — 1% on wealth above £10 million, 2% above £1 billion — pitched as a way to raise tens of billions while leaving most people untouched.

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What's being proposed

Under leader Zack Polanski, the Green Party has made an annual wealth tax its signature economic policy. The plan is a 1% yearly charge on an individual's net wealth above £10 million, rising to 2% on wealth above £1 billion. The party says it would raise roughly £15 billion a year, and pairs it with two related measures: aligning capital gains tax rates with income tax, and charging National Insurance on investment income. Together, the Greens claim those changes could raise north of £30 billion annually, which they would direct toward cutting energy bills and tackling child poverty.

Where it comes from

Since Polanski became leader, Green membership has more than tripled and the party has surged in the polls, with the wealth tax as its rallying call — repeatedly urging the Chancellor to "tax billionaires" rather than squeeze ordinary households. The policy has been especially prominent through 2026 as the Greens contested high-profile by-elections and mayoral races. Supporters point to polling suggesting around three-quarters of the public back the idea of a wealth tax in principle.

How it would work

  • Only individual net wealth above £10 million is taxed — assets minus debts, across property, investments, business holdings and so on.
  • The first £10 million is exempt. A 1% charge applies to the slice between £10m and £1bn.
  • Wealth above £1 billion is charged at 2%.
  • The vast majority of people — anyone below the £10m threshold — would pay nothing.
Because only the slice above £10m is taxed, the effective rate is always well below 1% until fortunes get very large. The calculator below shows the annual bill and the effective rate for any level of wealth.

The case for and against

Supporters argue

  • It targets only the wealthiest, leaving the overwhelming majority of households unaffected.
  • It could raise substantial revenue to cut bills and reduce child poverty without raising taxes on work.
  • Wealth has grown far faster than wages, and is currently taxed lightly compared with income.
  • The idea is broadly popular with the public.

Critics argue

  • The Institute for Fiscal Studies warns it could push internationally mobile wealthy people — and their capital — abroad, and discourage saving and investment.
  • Independent estimates of the revenue (around £9bn) are well below the party's £15bn claim.
  • Valuing illiquid assets like private businesses and art every year is administratively hard and disputable.
  • Several countries that tried annual wealth taxes later scrapped them, citing capital flight and high admin costs.
Interactive calculator

Estimate the annual wealth-tax bill

Enter a net wealth figure (everything owned, minus debts) to see the yearly charge under the proposed 1% / 2% rates, and the effective rate it works out to.

A what-if, not a forecast. Nothing here is law. This applies the Green Party's stated rates to a wealth figure you enter. It's a simplified estimate — a real scheme would have detailed valuation and exemption rules. Not financial advice.

Your figures

The proposed rates

Each rate applies only to the slice of wealth within that band.

The charge is modelled as a marginal, banded tax: 0% on the first £10m, 1% on wealth between £10m and £1bn, and 2% above £1bn, applied to an individual's net assets. Real-world design details — how assets are valued, what (if anything) is exempt, and how often — would materially affect the outcome and are not captured here. Revenue and behavioural effects are contested. Not financial advice.

Sources & further reading

Figures are illustrative and based on the party's stated proposals; revenue estimates are contested and rules could change. General information, not financial, legal or tax advice.