Zack Polanski has held the Green Party of England and Wales leadership since his September 2025 election on an eco-populist platform that drove sharp membership growth and local electoral gains. Recent scrutiny over a returned unlawful donation, questions on his primary residence and council tax, prior career claims, and internal party concerns about policy radicalism or electoral stagnation have created some leadership pressure. As of early September 2026, however, Polanski remains in post and has announced his intention to contest the Holborn and St Pancras by-election following Keir Starmer’s resignation, with local selection expected shortly. Trader assessments of an early exit hinge on whether by-election results, upcoming party conferences, or further internal motions shift sentiment toward a challenge or voluntary departure before any specified deadline.