PurposeThe present study aims to investigate the effects of sector 4.0 technologies, particularly Financial Technology (Fintech), on Sustainable Business Success (SBS) within the Indian garment sector. It aims to analyse the impact of Fintech Integration (IF) and Extent of Financial Knowledge (EFK) on sustainability performance, with a focus on understanding the mediating effect of Financial Accessibility (FA) in this relationship.Design/methodology/approachThe study utilizes covariance-based structural equation modelling (CB-SEM) to analyse data collected from 683 enterprises in the Indian garment sector. The theoretical frameworks of Ecological Modernization Theory (EMT) and the Resource-Based View are employed to guide the research.FindingsThe investigation reveals that Fintech Integration (IF) and environmental friendliness knowledge significantly impact the promotion and maintenance of sustainability within the Indian garment sector. Moreover, the study highlights the moderating influence of financial Accessibility (FA) on the associations among fintech integration, Extent of Financial Knowledge, and sustainability attainment. Furthermore, sensitivity studies demonstrate that improved financial access positively affects a firm’s sustainability performance.Originality/valueThis study contributes to the existing literature by addressing significant knowledge gaps and offering practical insights for managers and policymakers in the Ready-Made Garments (RMG) industry. It provides a comprehensive approach that integrates fintech and financial expertise to enhance credit accessibility and foster long-term viability for enterprises within the Indian garment sector. The originality lies in its holistic perspective, combining technological integration with the Extent of Financial Knowledge to drive sustainability in a specific industrial context, thus providing valuable guidance for industry stakeholders.