Social support and motivation to transfer are important components in conceptual models on transfer of training. Previous research indicates that both support and motivation influence transfer. To date, however, it is not yet clear if social support influences transfer of training directly, or if this influence is mediated by motivation to transfer. Conceptually, some models assume that motivation to transfer fully mediates the influence of social support on transfer (full mediation models), whereas other models also include direct relationships between social support and transfer of training (partial mediation models). In addition, some models specify finer sub-dimensions of social support, such as supervisor support, peer support, supervisor sanctions and feedback/coaching. What is the relative influence of these dimensions on the transfer of training? To what extent does motivation to transfer mediate the influence of different support dimensions and transfer? Aimed at answering these questions, the present meta-analysis (k = 32 studies, N = 5487 participants) examined the relationships between social support, motivation to transfer and transfer of training. Social support was conceptualized in four dimensions: supervisor support, peer support, supervisor sanctions and feedback/coaching. Meta-analytic structural equation modelling was used to test a partial mediation model and a full mediation model. Full mediation resulted in a better model fit. Peer support was the strongest predictor of motivation to transfer, and feedback/coaching was the strongest predictor of transfer of training. Theoretical and practical implications of the findings for developing conceptual models, measurement instruments and training interventions are discussed.