Postharvest losses (PHL) are a major problem in tomato supply chains, especially in tropical climates, as up to 40% of harvested fruits are estimated to decay along the chain. The study aimed at identifying which farmers' context characteristics, logistics and quality control activities relate with the generation of PHL in tomato supply chains, particularly in Zimbabwe. Commercial and subsistence tomato farmers (n = 197) from five major tomato-growing areas were analysed using a diagnostic tool to assess the status of logistics and quality control activities, the vulnerability of farmers' context, and the actual PHL. Hierarchical cluster analysis resulted in three clusters of farmers grouped based on similarities on context vulnerability and status of logistics and quality control activities. Spearman's rank correlation analysis and multiple linear regression analyses revealed that more advanced logistics and control activities, and context characteristics with a lower vulnerability to PHL are associated with less postharvest losses. The context characteristics, features of storage facilities, features of cropping system, and market price stability were significant determinants (p < .05) and explained 29% (Adjusted R2 = 0.287) of the variation in the PHL. The logistics control activity, determining processing volumes was identified as a possible determinant (p < .05) and explained 21% (Adjusted R2 = 0.205) of the variation in the observed PHL. The quality control activities, deciding on maturity to harvest, deciding on moment to harvest, and storage practices were the identified determinants (p < .05), which explained 23% (Adjusted R2 = 0.230) of the variability in the observed postharvest losses. A framework of intervention strategies tailored to tomato farmers' development stage is proposed to support them in a step-wise improvement of logistics and quality control practices to reduce PHL and advance towards more advanced supply chains.