Research shows that significant well-being disparities emerge between individuals who experience major negative events and those who undergo major positive events. However, such differences may vary among individuals. Drawing from the theory of the need for cognitive closure (NFC), we theorize and test whether NFC, which captures seizing and freezing on salient information to reach a fast conclusion, intensifies the differences in affective well-being between those who experience negative or positive events. Across three studies (total N = 2,399), we provide converging evidence that supports our theoretical claim. We first found that participants with high (vs. low) NFC show a greater affective well-being gap between those who recalled their past negative and positive major events (Study 1). We also discovered consistent patterns when participants were provided with negative or positive major event scenarios (Study 2). Lastly, we further substantiated our findings by utilizing a longitudinal study of the 20th presidential election in South Korea (Study 3). Over a 6-week period, the well-being gaps between the supporters of the election winner and the runner-up were more pronounced among individuals with higher NFC. Overall, our findings have implications for identifying a novel psychological trait that influences the affective well-being gaps following significant events in one’s life.