The regulation of road transport supply chains has recently become a subject of international concern. A significant body of research shows that ensuring minimum rates of pay for truck drivers is important, not only to workers’ health and safety but also to achieving improved road safety outcomes and other policy objectives related to the viability of the road transport industry. For this study, we used an empirical analysis to quantitatively demonstrate the impact of South Korea’s Safe Rates System on factors of the work environment and driver behaviours that affect road safety. Specifically, we looked at the impact of the system on market structure, truck drivers’ monthly net income, average working time, time spent on maintenance, and the frequency of overloading, speeding, and drowsiness while driving. Our results suggest that increased rates of pay for owner truck drivers resulting from the implementation of the Safe Rates System led to a reduction in the average number of contracting steps between client companies who ship goods and the truck drivers who transport them, improvement in the level of market transparency, increased monthly income, decrease in total time worked, decrease in the frequency of overloading, speeding, and drowsiness while driving, and increase in time spent on vehicle maintenance. The level of compliance with the system by clients and transport companies also had an overall positive impact on the industry structure. By empirically demonstrating the system’s impact, our results provide statistical evidence useful to the debate on reintroduction of the Safe Rates System in Korea.