Green shoots in the capital

London’s political map has been known to shift over the years, but the May local elections could underline a move to a more fragmented, multi-party landscape, with the Greens, Liberal Democrats and Reform UK all vying for space.

All 32 London borough councils are up for election. Labour remains the dominant force across the capital. However, the Greens will be buoyed by their recent victory in Gorton and Denton and the latest polling putting them on course to take the most council seats in London. Still, the question remains whether this momentum converts into council seats that could influence planning committees and housing policy, and to what extent the party is becoming more of a permanent fixture than a protest vehicle.

A challenge emerging on Labour’s left

In parts of London – particularly among younger, graduate, environmentally minded voters – the Greens are seen as a credible alternative. Since taking over as leader, Zack Polanski has overseen a surge in both membership and national polling. The party has reportedly grown from below 100,000 members to over 215,000, while recent polls place them between 14–17% nationally. This growth raises questions about whether the Greens are consolidating support among urban voters who have traditionally backed Labour.

That sense of growth is not confined to polling. I saw it directly when I attended the Green Party London Winter Conference in late 2025. The conference space was reportedly bigger than the spring event earlier in the year and members themselves seemed to be asking the question “since when were there this many of us?”

Polanski has framed the party’s message for May around inequality as well as climate, calling for higher wealth taxes and redistribution measures as a solution to improving living standards in London.

London calling

This election is about accumulation: more councillors, stronger second places and high-profile mayoral challenges. The Greens have momentum; May will show whether it converts into seats and potentially control of a small number of councils.

Polanski has been explicit about borough-level ambitions, with the Greens seeking “good gains” in Newham, Hackney and Lewisham, and “good progress” in Southwark, Haringey and Islington. That means expanding their councillor base, turning previously comfortable Labour wards into competitive contests, and embedding themselves firmly across inner London.

The Greens are openly targeting the Hackney mayoralty, with Zoë Garbett – Leader of the Green group on Hackney Council and London Assembly Member – positioned as a serious contender. A strong performance here would demonstrate how far the party’s local operation has developed.

In South London, ambitions are similar. In Lewisham, Green mayoral candidate Liam Shrivastava has centred his campaign on affordable housing delivery and local service priorities. This is a borough where Labour secured every council seat and the mayoralty in 2022, but the Greens believe voters are open to change.

Elsewhere, expectations are modest. In Greenwich, the party is not anticipating control of the council, but organisers are confident of increasing representation, particularly in the east of the borough, and in Southwark, the party will be hoping to capitalise on the defection of senior Labour councillor James McAsh to the Greens’ ranks. Ward-level advances, repeated across multiple boroughs, are how the Greens see London shifting in their favour.

Failure, by contrast, would look like stalled momentum. If target boroughs deliver modest vote share increases without additional seats – or if mayoral bids such as Hackney fall short without narrowing margins – questions may emerge about whether membership growth is translating into success.

Housing as the frontline issue

Unsurprisingly, housing dominated discussions at the Green London Winter Conference – the issue shaping London’s cost of living, particularly for the Greens’ target voters: young Londoners.

There was discussion about the structure of London’s housing market, including the role of private finance. The emphasis was not anti-development, but it demonstrated a scepticism about whether the current model alone can meet affordability pressures.

Debate centred on the Greens’ proposed solutions, which advocate a more active local role in delivery, stronger tenant protections, greater emphasis on council and affordable homes, and mechanisms to bring underused properties back into circulation.

So what?

The Green Party is increasingly influencing the housing and planning debate in London. As Labour’s national ambition of building 1.5 million homes faces difficulty, discussion may increase public interest in the Greens’ alternative solutions. That distinction is likely to feature prominently in doorstep messaging, particularly where frustration over housing costs is most acute.

May is unlikely to be the end of the story for the Greens in London. The party will want to show they can govern where they gain influence and build on success with future by-election gains before 2029.

For the sector, that matters. A larger Green presence in borough politics means a broader set of voices shaping the conversation around housing delivery, planning decisions and the balance between affordability, viability and growth. This may be most keenly felt in target seats like Hackney and Lewisham, where the Greens have the highest chances of winning, as well as through increased representation on planning committees across other boroughs.

Understanding that evolving political landscape – and how it may influence local decision-making over the coming years – will be increasingly important for those operating across London’s built environment.

Expert insight, intelligence gathering and knowledge sharing is in LCA’s lifeblood and ensures that our clients receive the highest quality strategic advice and counsel. Through regular and customised briefings and events, we help clients navigate through what can be a confusing and fast-changing landscape. If you’d like to discuss what any of these developments could mean for your organisation or your projects, contact us at insight@thisislca.com