Turnout in the 2024 UK General Election was the second lowest on record. Understanding why so many voters chose not to vote is important because low turnout undermines the legitimacy of democratic institutions and can contribute to political inequality. Using sixty years of British Election Study data, we examine trends in turnout in two steps. First, we examine changes in turnout across classic (class, urban-rural) and modern (education, age) political cleavages. Like voting behaviour, abstention is structured by political cleavages, as younger and working-class people are less likely to vote. We explore whether these gaps grew in 2024. Second, we compare the 2024 election with the record-low turnout election (2001), focusing on three main areas: perceived convergence of the main parties, the competitiveness of the election, and political alienation. This paper has critical insights for researchers and policymakers who are concerned with political engagement.