Utilizing a meta-analytical approach for testing moderating effects, the current study investigated organizational tenure as a moderator in the relation between affective organizational commitment and organizational citizenship behavior (OCB). We observed that, across 40 studies (N = 11,416 respondents), the effect size for the relation between affective organizational commitment and non-self measures of OCB was 0.23. However, we also found that organizational tenure moderated the relation in a non-linear way. Before 10 years of tenure, the strength of the commitment-OCB relation increased as organizational tenure increased; after that point, the strength of the commitment-OCB relation decreased as organizational tenure increased. In short, the moderating effect of tenure follows a curvilinear pattern. (Contains 1 table.)