Scholarly discussion on the amalgamation of sustainability and supply chain management has been growing in the last decade. However, an integrated social and economic sustainability performance measurement in supply chains is an emerging avenue in the Sustainable Supply Chain Management discourse. Hence, the purpose of this study is to understand how socially sustainable practices affect economic sustainability performances in supply chains. A survey questionnaire and a conceptual framework were developed to explore this relationship. Survey data collected based on responses from 119 managers in the Sri Lankan apparel-manufacturing sector was analyzed using Partial Least Square Structural Equation Modelling. We observed that the practices conducted by apparel manufacturers ensuring the social sustainability of the human factor inside the company (Internally influencing Social Sustainability Practices-ISSP) and in society (Externally Influencing Social Sustainability Practices-ESSP) create a positive impact on the economic performance. However, the effect produced by ISSP was higher compared to the ESSP. This study is based on a single developing country and, thus, should be extended to other countries considering the different institution environments when studying this interrelation between the social and economic sustainability dimensions.