In recent years, both businesses and academia have started to recognize sustainability as a crucial aspect of gaining a competitive advantage in the supply chain. This study aims to assess the effects of sustainable supply chain management (SSCM) practices on textile sectors’ sustainability performance. It also assesses how supply chain ambidexterity mediates the connection between SSCM, from a triple bottom line (TBL) standpoint, and firm sustainability performance outcomes. Using the resource-based view and stakeholder theories, the study employed 240 survey responses from firms operating in textile industry in Pakistan and the validity and reliability of the data were confirmed, and the hypotheses were evaluated, using PLS-SEM. The findings show that SSCM practices have a major favorable influence on Sustainability Performance (SP) and Supply Chain Ambidexterity (SCA). Furthermore, in Pakistan's textile industry, SCA acts as a mediator in the relationship between SSCM and Sustainability Performance. Through an analysis of the fundamental factors and connections that lead to the development of the intricate connection between SSCM practices from a triple bottom line viewpoint and a company's sustainability performance, this research contributes to the current literature on SSCM and SCA, especially in the context of Pakistan's textile industry, by identifying the mediation effect of SCA on SSCM and SP.