Managing the freshness of postharvest vegetables in the supply chain poses significant challenges. Freshness, a critical quality indicator, directly impacts the fitness for consumption and consumer purchasing decisions. Previous studies have identified various factors influencing vegetables’ freshness, including consumer perspectives, physiological characteristics, temperature management, and delivery time. However, limited research compares the factors across different stakeholders in the supply chain. This study aims to identify influential factors affecting vegetables’ freshness from the perspectives of producers, wholesalers, retailers, and transport providers. A stratified sampling survey was conducted with 151 respondents to identify key freshness determinants. Multiple linear regression analyses revealed that mode of transportation, delivery time, biological control, and temperature control significantly influence postharvest vegetable freshness. These factors were utilized to formulate a freshness score, an objective function for optimizing vehicle routing in vegetable distribution. The findings underscore the importance of integrating these criteria into supply chain practices to enhance freshness, reduce losses, and improve efficiency. Strategies proposed include best practices for postharvest storage and handling to preserve quality, extend shelf life, and minimize waste. To ensure efficient supply chain operations and higher consumer satisfaction, stakeholders must prioritize these critical factors. This research provides valuable insights into optimizing the fresh vegetable supply chain, contributing to improved sustainability and resilience.