This study investigates linear and non-linear associations among work tenure, organizational tenure, and organizational citizenship behaviors (OCB), and between leader–member exchange (LMX) and OCBs. A deductive approach was employed to collect data from academics. Using a convenience sample of 364 lecturers from six technical universities in Ghana, stepwise OLS regression analysis suggests that LMX correlates positively with OCBs. The relationship between work tenure and OCB was positive, with longer-tenured employees engaging in more OCBs. The effect of organizational tenure was, however, non-significant. Findings from this study have both theoretical and practical implications. Theoretically, this study adds to the literature on OCBs and LMX, and further enhances the understanding of how tenure in an organization can foster employee productivity. Practicaly, human resource practitioners and managers of higher education institutions can benefit from the findings of this study due to the implicit effects of both work and organizational tenure on workers’ attitudes, behaviors, and performance. This is a novel and pioneering study in an understudied context that examines work tenure, organizational tenure, LMX, and OCB in six public technical universities.