<p>While mobile payments have gained momentum globally, their adoption in retail business transactions remains limited in certain developing economies, even where users actively rely on the same systems for remittance transfers. This paradox reveals a critical gap in understanding the knowledge-based barriers that shape the digital economy: resistance to mobile payment adoption as a context-dependent phenomenon, shaped not by technological unfamiliarity but by a lack of applied knowledge and trust in specific transaction contexts. To investigate this complex economic issue, we conducted an exploratory, mixed-methods study involving semi-structured interviews with merchants (<i>n</i> = 40, Study 1) and focus groups with consumers (<i>n</i> = 82, Study 2) in Haiti. Our findings identify three core themes driving resistance at multiple levels of the economy. The first is Trust &amp; Ubiquity, which encompasses a lack of trust in the payment system itself, the technology provider, and the agents facilitating transactions. The second is Cost &amp; Preferences, involving transaction costs and a pronounced preference for cash among both consumers and merchants. Finally, Risks &amp; Economic Advantages includes perceived financial and privacy risks, combined with a lack of compelling economic benefits. These factors were found to positively influence resistance and negatively affect willingness to adopt mobile payments for business-related transactions. A key theoretical contribution of this study lies in its extension of Innovation Resistance Theory by demonstrating how resistance is not only attitudinal but also a mutual and relational dynamic that hinders innovation. We identify a bidirectional mediation loop between merchants and consumers, in which each group’s resistance and preference for cash transactions appear to mutually reinforce the other’s reluctance to adopt mobile payments, stifling the knowledge diffusion crucial for a vibrant digital economy. Additionally, we show that trust is transaction-specific, highlighting the need for a more nuanced understanding of trust in digital financial systems. By situating resistance within the informal economy of a cash-dependent, low-trust environment, this research advances the conceptual boundaries of the Innovation Resistance Theory. It offers practical insights for policymakers and service providers seeking to leverage innovation to solve complex problems in economic development and foster a sustainable, inclusive knowledge economy in similar contexts.</p>