The significance of recognizing social sustainability practices for the successful management of projects is increasingly acknowledged. However, to what extent these practices are actually implemented within project management has not been sufficiently addressed in the literature. To address this gap, an empirical study was conducted to investigate the usage of social sustainability practices and explore any disparities in their implementation between domestic and international construction firms in the United Arab Emirates. This study employed a mixed-methods approach, combining interviews and a structured questionnaire. Through the interviews, 32 social sustainability practices were identified. Subsequently, a questionnaire was used to collect data from project managers representing 259 firms. The analysis revealed several key findings: 1) social sustainability practices are adopted at varying rates; 2) twelve practices, primarily concerning fundamental human rights and labor ethics, are uniformly employed by both domestic and international firms; and 3) international firms are more likely than their domestic counterparts to regularly implement the other 20 social sustainability practices. These findings develop new knowledge on the implementation of social sustainability practices and advance the understanding of how firm origin influences the adoption of these practices. Additionally, the findings and their implications provide valuable guidance for policymakers and project leaders looking to incorporate social sustainability practices into their operational strategies.