Green Party manifesto: the pledge, the price, the payer

The Green Party manifesto, in the sense most people mean when they search for it, is a set of proposals built around four ideas: a new annual tax on wealth, a tougher tax treatment of investment income, a cap on private rents and a larger role for the state in energy, banking and public services. The party presents these as the route to cheaper bills and fairer public finances.

Existing coverage of Green Party policies explains what the party proposes. It does not count what the proposals would cost, or who would pay. That is the purpose of this article.

Main points

• As to the wealth tax: the party proposes a levy of 1 per cent a year on wealth above £10 million and 2 per cent above £1 billion, which its leader has said would raise somewhere between £15 billion and £25 billion a year.
• As to investment income: the party wants capital gains taxed at the same rates as earned income and wants National Insurance applied to investment income, which raises the cost of saving and investing.
• As to rents: a three-year "emergency brake" would stop private rents rising faster than the lowest of inflation, wage growth or 2 per cent.
• As to energy: the leader has called for a guarantee that household energy prices will not rise, and has spoken of setting aside £8.4 billion for that purpose, without a costed mechanism to pay for it.
• As to ownership: the party favours returning public services to public hands and has backed a publicly owned retail bank.
• As to the evidence: the history of net wealth taxes in advanced economies is a history of repeal, and the history of rent controls is a history of shrinking supply.

Green Party policies in summary

Readers searching for the Green Party policies, or asking what the Green Party stands for, will find that it combines environmental goals with a wide programme of redistribution. The party's leader, Zack Polanski, has described the wealth tax as a first-day priority. The party has also proposed bringing capital gains tax into line with income tax, and attaching National Insurance to investment income. At its 2026 conference it added an emergency cap on private rents.

We have used the party's published policies and the statements of its leadership throughout, since the policy position of a political party is a matter of public record. Where a figure is the party's own, we say so.

The "wealth tax" that is really a transfer

The party describes its wealth tax as a "fair share" from the very richest. It is nothing of the kind. It is a recurring annual charge on assets that have already been taxed when they were earned, saved and invested, and it applies whether or not those assets generate any income to pay it.

That distinction matters. An income tax is paid from income. A wealth tax must be paid from the capital itself, or from the sale of the assets, and for owners of businesses this can mean selling shares in the very firms that employ people. The money does not come from nowhere. It comes from investment that would otherwise have been made.

The party's headline figure is about £15 billion a year. There is, of course, a fair debate about whether the very wealthy contribute enough. It is for the electorate to decide. But a figure is only as good as the behaviour it assumes. If those subject to the tax move assets or residence, the revenue falls, and the burden shifts to those who cannot move.

What history says about wealth taxes

The cautionary evidence is considerable. According to the OECD, the number of member countries levying an annual net wealth tax fell from 12 in 1990 to 4 in 2017. Austria, Denmark, Germany, the Netherlands, Finland, Luxembourg and Sweden all abandoned theirs, mostly because they raised little, cost a great deal to administer and encouraged capital to leave. France replaced its broad wealth tax in 2018 with a narrower charge on property.

The reasons are not hard to find. Wealth is mobile, valuations are contested, and the cost of compliance is high. A tax that raises less than promised leaves a hole, and the hole is filled by taxes that fall on those who cannot easily avoid them: employees, pensioners and small businesses.

The household bottom line

Put simply, the arithmetic does not favour ordinary households. Take the party's own £15 billion figure. Spread across roughly 28 million UK households it is about £535 per household per year. That is the sum the programme hopes to collect from a few thousand people. If it falls short, as wealth taxes historically have, the shortfall is met by everyone else, or by borrowing, and borrowing is dearer when gilt yields sit around 5 per cent.

Add the effect on investment. Higher taxes on capital gains and investment income reduce the return on savings, and the pensions that rely on them. A policy sold as a levy on billionaires reaches the pension fund and the small shareholder as well.

Rent controls: the promise and the supply

The proposed three-year cap on private rents is presented as relief for tenants. It is nothing of the kind. It is a transfer from landlords to sitting tenants that does nothing to build a single new home. Where rents are held below the level that clears the market, landlords have less reason to let, to maintain or to invest. New tenants, and those who have not yet found a home, bear the cost in the form of fewer properties and stiffer competition for those that remain.

The international record is consistent. Rent control reduces the supply of rental housing over time and favours those already in occupation. The real remedy is supply, which means planning reform and building. A cap on rents is a way of treating the symptom while the disease advances.

Energy: a guarantee without a payer

The party has called for a guarantee that energy bills will not rise. A guarantee is not a policy. It is a promise that someone else will pay. Somebody must meet the difference between what energy costs and what consumers are allowed to be charged, and that somebody is the taxpayer. An £8.4 billion allowance covers a few months at best.

The deeper problem is that subsidised and intermittent renewables behave, in the society's analysis, like a regressive tax on low-income households, who spend a larger share of income on energy. Policies that raise the system cost of power and then cap the price at the meter do not abolish the cost. They move it to the Exchequer, and the Exchequer sends the bill to the taxpayer.

Public ownership and the balance sheet

Bringing public services back into public hands sounds simple. In practice it means the state taking on the assets and the liabilities of the businesses concerned, along with the investment those businesses need. A publicly owned retail bank would add a large new exposure to the public balance sheet, in a country where the cost of servicing the national debt is already among the largest items in the Budget.

The question to ask is not whether public ownership is attractive in principle. It is whether the taxpayer wishes to carry the risk, and what the opportunity cost would be. Every pound tied up in a state-owned bank is a pound not available for hospitals, schools or tax cuts.

Best case, worst case

In the best case, the wealth tax raises most of what the party hopes, avoidance is limited, and the revenue pays for the energy guarantee and a modest expansion of public services. Even then, the programme would rest on a narrow tax base, and a narrow tax base is a fragile one.

In the worst case, capital and entrepreneurs leave, the tax raises a fraction of the headline figure, rents are capped while supply falls and the cost of public ownership is added to the national debt. The shortfall falls on households, and the party's programme becomes an illustration of how a wish-list meets the arithmetic.

What should be done

The prescription is not an abstract one. The party's concerns about the cost of living are legitimate. But the remedy lies in growth, which means lower taxes on work, saving and investment, planning reform to build more homes, and a stable energy supply that does not depend on subsidy. These measures would raise living standards without raising anyone's tax bill.

It is, of course, for the electorate to decide which programme it prefers. But the Green Party manifesto, as it stands, deserves to be read with a calculator in one hand.

Frequently asked questions

What are the Green Party policies? The party's main economic proposals are an annual wealth tax of 1 per cent above £10 million and 2 per cent above £1 billion, higher taxes on capital gains and investment income, a temporary cap on private rents, an energy price guarantee and more public ownership.

What does the Green Party stand for? The party combines environmental goals, such as faster decarbonisation, with a wide redistributive programme. It favours higher taxes on wealth and capital, greater state involvement in energy and banking, and stronger protection for tenants.

How much would the Green Party wealth tax raise? The party's own figure is about £15 billion a year, and its leader has suggested a range of £15 billion to £25 billion. Critics argue that avoidance and emigration of assets would reduce the yield, as happened in other countries.

Would Green Party policies raise taxes for ordinary households? The headline taxes fall on the wealthy, but higher taxes on investment income and capital gains reach pension funds and small investors, and any shortfall in revenue would have to be met by others or by borrowing.

Conclusion

The Green Party manifesto offers a clear programme, and clarity deserves credit. But a programme is not a plan until it has been costed, and costed against the behaviour of real people and real markets. On the available evidence, the pledge is generous, the price is high and the payer is the household.

Every promise has a bill. The only question is who receives it.