This study investigates the role of big data analytics capabilities (BDAC) in enhancing sustainable supply chain performance (SSCP), with supply chain agility (SCA) as a mediating mechanism. We consider BDAC as a higher-order construct that includes management, personnel and infrastructure capabilities, drawing on the Resource-Based View (RBV) and Dynamic Capabilities theory. Using survey data from 155 supply chain professionals across manufacturing, retail, logistics, and services, structural equation modeling (PLSSEM) was applied to test hypotheses. Results show that BDAC and its dimensions significantly enhance SSCP and SCA, with SCA partially mediating these relationships. The model demonstrates strong explanatory (R² = 0.62) and predictive power (Q² = 0.50). This study contributes theoretically by integrating BDAC, agility, and sustainability into a unified framework, and practically by offering firms guidance on leveraging analytics for sustainable supply chain outcomes.