Carpooling is emerging as a sustainable transport mode because of promising benefits in reducing carbon emissions, traveling costs, traffic congestion, etc. However, encouraging car drivers to offer carpooling services in developing countries is challenging due to no proper studies background. Therefore, this study investigated the determinants of carpooling adoption as drivers (not passengers) toward sustainable mobility in an emerging economy. The study used the primary dataset of 180 observations gathered at Thammasat University, Pathum Thani, Thailand. The sample data were analyzed using Structural Equation Modeling (SEM). The binary carpooling choice (i.e., offering and not offering) was used as the endogenous variable. The incentive attributes (hypothetical), sociodemographic characteristics, travel-related variables, and primary reasons for private car use were considered as the exogenous variables. The highlighted findings identified incentive attributes as potential determinants to incline car drivers to offer carpool rides. Female married and the 18–39-year group were more inclined to adopt carpooling than males, unmarried and the ≥40-year group, respectively. Household car ownership increases the likelihood of carpooling while motorcycle ownership does otherwise. Drivers who use private cars on account of privacy and non-availability of public transport are more inclined to offer carpool rides. Also, the study presented policy implications for carpooling adoption as drivers based on the multivariate statistical analysis. The findings enhanced the direction for carpooling adoption for educational trips toward sustainable mobility.