This preregistered meta-analysis (k = 113, total n = 93,668) addressed how the Big Five dimensions of personality (extraversion, agreeableness, conscientiousness, neuroticism, and openness) are related to loneliness. Robust variance estimation accounting for the dependency of effect sizes was used to compute meta-analytic bivariate correlations between loneliness and personality. Extraversion (r = -.370), agreeableness (r = -.243), conscientiousness (r = -.202), and openness (r = -.107) were negatively related to loneliness. Neuroticism (r = .358) was positively related to loneliness. These associations differed meaningfully in strength depending on how loneliness was assessed. Additionally, meta-analytic structural equation modelling was used to investigate the unique association between each personality trait and loneliness while controlling for the other four personality traits. All personality traits except openness remained statistically significantly associated with loneliness when controlling for the other personality traits. Our results show the importance of stable personality factors in explaining individual differences in loneliness.