Green Leader Zack Polanski to Push for Three-Year Cap on Private Rent Increases at Party Conference

Green Party of England and Wales leader Zack Polanski will use his keynote address at the party's annual conference in Brighton on Friday to demand a temporary nationwide ceiling on private rent hikes, framing housing affordability as a defining test of fairness between generations.

According to advance extracts of the speech, Polanski will urge the government to impose a three-year "emergency brake" that would prevent private landlords from raising rents by more than the lowest of three benchmarks: the consumer price index measure of inflation, average wage growth, or 2%. The proposal is designed to give tenants immediate relief while ministers develop a longer-term mechanism the Greens call a national Fair Rents Guarantee.

The intervention signals that the Greens intend to keep housing at the centre of their political offer, even as the party seeks to broaden its appeal beyond its traditional environmental base. By pitching the policy as a generational fairness issue, Polanski hopes to tap into widespread anxiety among younger voters who feel locked out of stable, affordable accommodation.

In his remarks to activists, the Green leader is expected to describe a country in which adults of all ages remain dependent on their parents because of the cost of renting. He will point to 19-year-olds commuting long distances to university, 25-year-olds unable to take jobs in expensive cities, and even 35-year-olds moving back in with parents alongside their partners.

Polanski is expected to argue that landlords have for too long been free to push rents far beyond what tenants earn, leaving renters with little choice but to absorb the increases and cut back on other essentials. A temporary slowdown, he will say, would provide "vital breathing space" for households and buy time for a more durable affordability framework.

The conference, which the party describes as its largest ever, comes after the Greens announced earlier this year that membership had tripled since Polanski became leader just over a year ago. The gathering in Brighton is also taking place against a backdrop of significant electoral momentum: the party gained hundreds of council seats in England's local elections earlier this year and secured a fifth MP, Hannah Spencer, in the Makerfield by-election.

Yet there are signs that the party's surge in national polling may have plateaued in recent months. The Greens also face difficult strategic questions about how to respond to Labour's change of leadership under Andy Burnham, who has shifted his party's position in several areas where the Greens had previously seemed to hold the advantage.

In an interview ahead of the conference, Green co-deputy leader Rachel Millward acknowledged that Labour was now "rhetorically, on a much more similar ground" to her party. She cited Burnham's move towards electoral reform, a long-standing Green demand, and his openness to a much closer future relationship with the European Union as examples of the political convergence.

Labour has also announced sanctions on Israeli West Bank settlements deemed illegal under international law and reopened a scheme to resettle refugees. Polanski claimed ahead of the conference that both policies resulted from the electoral pressure his party has applied to Labour, suggesting the Greens are influencing the national agenda even without holding power at Westminster.

The timing of the conference, however, creates an awkward logistical challenge for Polanski, who is standing for the Greens in next week's Holborn and St Pancras by-election. The contest in the central London seat was triggered by former Labour prime minister Sir Keir Starmer's decision to leave Parliament, and it represents a major opportunity and a significant risk for the Green leader.

Polanski said last week that he intends to return "straight back" to the constituency after delivering his leader's speech, and he has even urged party activists to leave the conference over the weekend to help him campaign. Victory would give the Greens their first seat in the capital, but it would require overturning a huge Labour majority from the 2024 general election.

The rent cap proposal is likely to reignite debate over the economic effects of rent controls, a policy the Greens have long championed. The Institute for Fiscal Studies has previously warned that such measures can produce unintended consequences, including demand exceeding supply in the rental market as landlords withdraw properties or reduce investment in new housing.

Millward rejected that concern during an appearance on BBC Breakfast, arguing that most landlords are "super-earners" who make more money than those in other sectors and "would be able to absorb a slight reduction in rent." Her comments reflect the party's broader position that the rental market is not a perfectly competitive one and that intervention is justified to protect tenants.

The political context for the Green proposal includes the government's Renters' Rights Act, brought in earlier this year. Under that legislation, landlords can only increase rent once a year to the property's open market rate. The Act also makes tenancies rolling rather than fixed term and makes it harder for landlords to evict tenants.

Polanski is expected to argue that those reforms, while welcome, do not go far enough in ending the "fear and uncertainty" faced by millions of private renters across the UK. According to the Office for National Statistics, average UK monthly private rents rose by 3.5% to £1,377 in the 12 months to January 2026, underscoring the scale of the affordability challenge.

By proposing a three-year emergency brake, the Greens are positioning themselves to the left of Labour on housing and seeking to own an issue that resonates strongly with younger voters and renters in urban constituencies. Whether the party can convert that positioning into parliamentary seats, beginning with Holborn and St Pancras, will be a key test of its political trajectory in the months ahead.