THE IMPACTS OF PIX ON MERCHANT DISCOUNT RATES

This study quantitatively analyzes the impact of Pix adoption on the pricing of average merchant discount rates (MDR) charged to merchants in the Brazilian acquiring market, focusing on credit and debit functions. The introduction of Pix by the Central Bank of Brazil in November 2020 represented a structural shift in the Brazilian payment system, leading to changes in consumer and merchant behavior. To investigate the effects of Pix on MDR, an econometric model was built using multiple linear regression with quarterly data from 2011 to 2024. The model incorporates control variables for events relevant to the acquiring market during the period, such as the COVID-19 pandemic and the regulation imposing a cap on debit card interchange fees (TIC), in addition to seasonal variables and the basic interest rate (SELIC). The effects of Pix adoption are analyzed through a continuous variable that captures its progression over time, based on previously validated assumptions. The results suggest that the expansion of Pix significantly accelerated the decline in debit MDR, while providing limited evidence of impact on credit MDR. Structural factors such as the pandemic, TIC regulation, and the SELIC rate were also found to influence the behavior of merchant discount rates. The empirical analysis contributes to the understanding of how new payment arrangements impact already consolidated markets, offering insights for companies in the sector to design strategies that are better aligned with the emerging landscape of competition and innovation. In this regard, the proposed model proves useful for industry operators, regulators, and researchers interested in the evolution of the Brazilian financial system.