This paper explores the effects of customs policies on supply chain performance in Jordanian small and medium-sized enterprises (SMEs). The success of SME supply chains is a strategic imperative for inclusive economic development in Jordan, where they serve as key engines of growth and employment. Unfortunately, many administrative barriers are intrinsic to inefficient customs protocols which severely handicap the abilities of SMEs. The research uses the SEM-PLS analysis on 197 of SMEs directly involved in customs clearance, logistics and allied activities traded to gather field survey via spread this study among employees as partake. The resulting findings suggest that effective, transparent and long-term focused customs systems are drivers of SME success in their supply chains over key dimensions such as cost effectiveness, agility and service experience. Further, sustainability adoption completely mediates the latent between customs incentives and supply chain performance improvements. Therefore, rational customs reforms championing environmental consciousness can significantly boost productivity, competitiveness and resilience of Jordanian SME supply chains. Both public policymakers and SME managers can apply these valuable evidentiary conclusions to craft customized administrative protocols and strategic responses attuned to the unique needs and constraints facing smaller Jordanian enterprises. Ultimately, supportive customs environments provide crucial launchpads for unlocking the fullest potential of SMEs.