The progress and diffusion of next-generation digital technologies are having an enormous effect on industries, innovation, and society. Innovative mobile transaction platforms are becoming the dominant payment system in major emerging economies. This study focuses on estimating the future trend and analyzing the pattern and rate of adoption of the Unified Payments Interface (UPI) in India. UPI is not only decreasing the share of credit and debit cards and other payment modes but also reducing the reliance on cash in the economy. The main aim of this study is to estimate the future trend and analyze the pattern and rate of adoption of UPI in India. Utilizing the S-shaped growth cycle, we discuss the technology diffusion models and find that the Harvey model fits the data better than the Logistic and Gompertz ones. UPI transactions is likely to increase from 45.97 billion in 2021-22 to 643.76 billion in 2030-31. Further, monetary value of UPI transactions is also projected to grow sharply, from Rs.84.18 trillion in 2021-22 to Rs.835.77 trillion in 2030. Thus, UPI driven expenditure per person per day is likely to increase from Rs.165 in 2021-22 to Rs.1500 in 2030 Results predict that UPI based transactions is likely to increase at manifold levels, both in volume and value terms, having important implications for the economy, especially for payments app developers, internet service providers, the national regulatory agencies, particularly in view of UPI security related risks.