The Green Party has seen a notable increase in public support since Zack Polanski became leader in September 2025, with an average rise of four points in opinion polls. According to The Guardian's latest poll tracker, the party now stands at 13.5%, just five points behind Labour on 18.6%. This so-called 'Polanski effect' has given the Greens a surge of momentum and visibility in an increasingly fragmented political landscape.
However, experts caution that the data is not uniform across all polling firms. January polls from YouGov and Find Out Now put the Greens at 17%, while Focaldata, More in Common, and Survation recorded figures of 10% and 11% respectively. These discrepancies may stem from differences in methodology, such as whether the Greens are included as an option in surveys, or from varying assumptions about voter behaviour.
Age remains a key factor in Green support. Among 18- to 24-year-olds, backing for the party has jumped from 26% in early September to 45% in mid-January, according to YouGov. Professor Sir John Curtice of the University of Strathclyde warned that this demographic shift could hurt Labour, particularly in London's local elections in May, as the Greens appeal to young, middle-class professionals who traditionally vote Labour.
The cost of living is the top concern for all Green supporters, but new voters—those who did not vote Green in 2024—place greater emphasis on the economy and Brexit, while Gaza is less important to them. Climate change is a lower priority for new supporters (7%) compared with existing ones (12%). Adam McDonnell of YouGov suggested the Greens may need to focus on economic messages to appeal to these new, relatively affluent and highly educated voters.
Ipsos polling indicates that Green supporters align with Liberal Democrat and Labour voters on defence and the NHS, but are more concerned about inequality and hold relaxed views on immigration. They also display an anti-establishment streak, being more distrustful of authority and critical of the wider system. Curtice noted that with Polanski and Reform UK leader Nigel Farage on the national stage, both charismatic leaders offer clear visions that contrast with conventional politicians.
