Britain faces a dramatic political realignment, according to the first YouGov multilevel regression and post-stratification (MRP) model since the 2024 general election. The poll, conducted in late June 2025, showed Reform UK leapfrogging both Labour and the Conservatives to become the largest party in Westminster, but stopping well short of a parliamentary majority. This scenario underlines how volatile and fragmented the British political landscape has become, with no single group commanding clear support from the electorate.

YouGov’s projections give Reform UK 271 seats, followed by Labour with 178 and the Liberal Democrats on 81. The Conservatives slump to 46, while the Scottish National Party claims 38, and both the Greens and Plaid Cymru are set to win seven seats each. A party needs 326 seats for a majority in the 650-seat British Parliament.

Notably, the combined Labour and Conservative vote share drops to just 41%, down sharply from 59% in the 2024 election, a sign of deepening public disaffection with the established parties. Reform leads in most English regions, as well as in Wales, marking an unprecedented redrawing of the electoral map.

The figures suggest that 97% of simulations end in a hung parliament, with Reform winning the most seats in 99% of outcomes. Even a hypothetical Reform-Conservative coalition would reach only 317 seats, leaving them short of the 326 needed for a majority. A five-party alliance of Labour, the Liberal Democrats, SNP, Greens, and Plaid Cymru would clear the line in just a quarter of scenarios. In a further sign of instability, seven serving cabinet ministers would lose their seats under these projections.

With winning vote shares averaging just 35% and margins shrinking, the model points to an era of intense electoral volatility. Britain now finds itself facing a parliament likely defined by deal-making, weak mandates, and a fractured political centre.