Previous studies that have investigated associations between working memory (WM) and the Big Five personality traits have yielded mixed results, with some finding statistically significant associations while others have not. The aim of the current study was twofold. First, we systematically reviewed previous studies on WM-Big Five associations. Second, we investigated associations between three WM composites (numerical-verbal WM, visuospatial WM, n-back) and the Big Five in a large-scale study on adults (n = 503). Here we controlled for possible confounding caused by the way WM is operationalized, the content domain of the WM tasks (verbal vs. spatial), and sample size. The systematic review revealed that the majority of earlier studies show no association between any of the personality traits and WM performance. As regards our empirical study, the only significant associations were the negative correlations between n-back WM updating performance and the Conscientiousness and Openness traits. This means that the more Conscientious or Open to experiences a participant reported being, the worse was the n-back performance. Overall, our study failed to show any robust relationships between WM performance and the Big Five personality traits. We discuss possible reasons for these findings.