The Green Party has found itself at the centre of a political moment that few anticipated. As Labour grapples with rolling crises, Reform reshapes the right, and the Liberal Democrats rebuild in their historic heartlands, a clear opening has emerged in England’s urban, progressive centres.

Andrew Clark pens his thoughts on what this could mean for London.

The Green Party’s victory in the Gorton & Denton by‑election, in a seat the party openly admitted was not a primary target, represents a seismic shift on the left of British politics.

All the pre‑election commentary focused on a Labour vs Reform contest, yet the Green Party not only beat their polling expectations but won outright.

For London, this result matters. 

The demographic and political profile of Gorton & Denton, young renters, multicultural communities, and a strong progressive vote, is strikingly similar to many inner London boroughs, including Hackney, Lewisham, Islington and parts of Camden. These areas are already targets for the Green Party in the coming elections and the result in the by-election will likely see them redouble their efforts as May approaches.

London Momentum: Why the Green Party Are Now Serious Contenders

While national polls put the Green Party at around 17%, their London support is significantly higher, and although precise figures fluctuate, the party is well‑placed to become a major political player in London.

This represents a dramatic reversal of fortunes. In 2022, the Green Party secured only 11 councillors out of more than 1,800 seats up for election across London, yet they now credibly threaten Labour dominance in several inner‑city boroughs.

Where Could the Green Party Win?

Hackney: the number one target

Hackney remains the Green Party’s top London target. The party has been growing prominence here for over a decade and, despite winning more than 20% of the vote in 2014, failed to secure a single seat.

The directly elected Mayoralty gives the Green Party their best-ever chance of taking control, though they are less likely to secure a full council majority, meaning key committees like planning and licensing could be highly unpredictable.

Lewisham: once rock-solid Labour, now in play

Until recently, Lewisham was considered untouchable for Labour, winning over 60% of the vote and every council seat.

But with favourable demographics, no strong alternative opposition, and a London‑wide Green Party surge, the party now sees Lewisham as a genuine opportunity, especially with the mayoral structure offering a direct route to power.

While Labour will still expect to win in Lewisham, the Gorton & Denton result should serve as a warning that the local party need to be hyper-focused on shoring up their core vote.

Lambeth: expanding beyond historic pockets

The Green Party have held seats in Lambeth since 2006, but struggled to make significant gains outside a small number of wards.

In 2026, they are campaigning hard across Herne Hill, Streatham St Leonards, and now Brixton, traditionally Labour’s safest territory.

However, the resurgent Liberal Democrats, particularly across Waterloo, Stockwell East and Vauxhall, make it difficult for the Green Party to make the kind of gains they would need to push Labour out of control of the council.

2026 will likely see a complex three-way contest for the borough, and while Labour will be confident of victory, their total dominance in Lambeth will be challenged.

Southwark: a crowded battlefield

The Green Party are strongly contesting Nunhead, Peckham Rye, St Giles, Goose Green and Rotherhithe, seats where Labour hasn’t needed to campaign in the past. In the north of the borough, the Liberal Democrats will seek to fully regain their historic strongholds along the river.

Expect fragmentation rather than outright change, but with significant implications for planning committees.

Where else?

Expect the Green Party to also pick up seats in Islington, Haringey, Waltham Forest, Newham, Greenwich, and Camden.

What does this mean for development?

A surge in Green Party councillors could significantly impact the politics of planning across inner London.

While there is an expectation that Green Party councillors will be focused on the design and environmental elements of development, and they will, the political focus and sentiment of the party has shifted considerably in recent years.

The Green Party has become the leading political voice in the capital, pushing back against private-sector-led development.

The political leadership of the Green Party nationally, and much of their activist base in local authorities, are highly active in anti-development campaigns or organisations pushing for development that is delivered at entirely social rent levels, led by councils rather than the private sector.

Any administration seeking to bring forward public/private sector joint ventures to deliver development, particularly estate regeneration, could find council plans for development reassessed or ended entirely should the Green Party take control of councils in May.

The Green Party would also stiffen resistance to Green Belt and ‘grey belt’ release, favouring brownfield‑first development and smaller, sensitive infill projects. 

It is critical that the development sector fully understands what the modern Green Party is thinking when it comes to development and regeneration, and does not fall into the trap of equating the Green Party of 2026 with the Green Party of old.

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