Playing the System: Electoral Bias in the 2024 UK General Election

The UK's 2024 general election was the least proportional of modern times. Labour's substantial parliamentary majority rested on the smallest ever winning party vote share. The Conservatives, meanwhile, suffered one of their worst ever results. While political and economic events during the 2019–2024 Parliament were key to the outcome, the operation of the first past the post electoral system was also important. In 2024, it was strongly biased in Labour's favour and against the Conservatives, contributing substantially to the scale of their defeat and of Labour's victory, allowing Labour to parlay modest support into a large majority. This pro-Labour bias was to a large extent a result of the much greater efficiency of Labour's geography of support. We place the relative Conservative-Labour bias at the 2024 contest into a longer historical perspective, demonstrating that it marked the abrupt end of a ten-year period in which electoral bias had favoured the Conservatives.