This research investigates the transformative impact of the Unified Payments Interface (UPI) on the socio-economic landscape of Goa, focusing on the intersection of consumer behaviour and micro-enterprise sustainability. Utilizing a descriptive and analytical research design, the study analyzed 339 valid responses from a diverse sample of 176 individual consumers and 163 small business owners. The findings reveal a significant "generational inversion," where transaction frequency is highest among tech-savvy younger cohorts but intensity peaks in the 26–50 age group. A critical "rural trust ceiling" was identified, with geographical location significantly influencing security perceptions. From a business perspective, the study demonstrates that UPI adoption serves as a strategic growth driver, with 92% of merchants reporting expanded customer reach and improved operational efficiency through reduced cash-related risks. However, universal resistance to transaction fees across all occupations suggests that the current "Zero-MDR" model is vital for continued adoption. Despite the digital surge, infrastructure bottlenecks—specifically network instability and transaction failures—remain the primary deterrents. The study concludes that for UPI to achieve total financial inclusion, stakeholders must address the rural digital divide and stabilize technical infrastructure while maintaining the current cost-free framework.