Despite increasing interest in populism across Western Countries, there is limited research examining long-term individual factors influencing changes in populist attitudes over time. Existing longitudinal analyses of populist attitudes have shown inconsistent findings regarding variability and stability. Age has been cited as an influencing factor, showing that younger individuals are more prone to populist attitudes, and older individuals remain less affected and also, research has overlooked the role of life transitions in shaping populist attitudes. This paper addresses this gap by examining how life transitions—defined as discrete, time-bounded changes in life status with potentially long-term consequences (George, 1993)—affect populist attitudes. Previous studies have explored economic aspects of life transitions but have not adopted dynamic, longitudinal approaches (Kriesi & Pappas, 2015; Zagórski et al., 2021). To advance understanding, this study focuses on specific life transitions related to living arrangements, such as emancipation, returning to the parental home, living alone, and separation from a partner. Using panel data from Spain (2014–2024), this paper employs fixed-effect linear regression models to analyse the influence of life transitions on populist attitudes. Findings reveal that transitioning to living alone has a more substantial effect on populist attitudes than other transitions, such as emancipation or cohabitation with a partner. This research introduces a novel theoretical framework, emphasising the dynamic impact of life transitions on populist attitudes, thereby offering new insights into individual-level changes over time. By bridging the gap between populism and life-course research, this study highlights the importance of living arrangements in understanding populist trends.