Purpose Premised on the assertion that financial digitalization is currently the panacea and game changer in delivering progress towards the sustainable development goals (SDGs) through universal financial inclusion, especially in developing countries, the purpose of this paper is to establish the moderating effect of transaction tax exemptions in the relationship between mobile money adoption and usage and financial inclusion. Design/methodology/approach A semi-structured questionnaire was used to collect data from 379 micro, small and medium enterprises (MSMEs), which use mobile money services drawn from the Northern District of Gulu in Uganda to provide responses for this study. The predictive relevancy and the effect size of the model were determined by running partial least square algorithm through structural equation model (SEM) with 5,000 bootstrap samples in SmartPLS-SEM 3.0. Findings The findings indicated that all the latent variables of transaction tax exemptions showed significant and positive impact on mobile money adoption and usage to advance financial inclusion in developing countries. Moreover, when combined together, the overall SEM predictive model revealed a significant moderating effect of transaction tax exemptions in the relationship between mobile money adoption and usage and financial inclusion. This implies that transaction tax exemptions on digital financial innovations such as the mobile money services can stimulate economic growth through increased level of financial inclusion labeled as the main enabler in achieving the SDGs by the year 2030. Research limitations/implications Whereas data were collected from users of mobile money services, the samples were drawn specifically from MSMEs’ owners located in the Northern District of Gulu in Uganda. Thus, users located in other districts were not included in the sample for this study. Similarly, this study limited itself to only financial services offered through the mobile money platform. It ignored other digital financial channels such as the internet and electronic banking. Practical implications Going forward, in order to improve the economic well-being of households at the “bottom of the pyramid,” governments in developing countries should embrace the significant role of transaction tax exemptions in promoting digital financial innovations such as the mobile money services for increased level of financial inclusion. The governments in developing countries where mobile money has greatly spurred financial inclusion should not only reduce the existing transaction taxes on mobile money services but scrap it off in order to champion progressive increase in the level of universal financial inclusion prescribed as a key enabler in eliminating global poverty, especially in developing countries. Originality/value This study hints on the moderating effect of transaction tax exemptions in the relationship between mobile money adoption and usage and financial inclusion. The paradox in the current trends on transaction taxes on mobile money services, especially in developing countries remain a dearth in the nascent global FINTECH ecosystem.