The Impact of Digital Inclusive Finance on the High-Quality Development of County Economies and Its Spatial Effects: Evidence from the County Economies of Jiangsu Province, China

Using panel data from 40 counties in Jiangsu Province covering the period 2016–2023, this study proposes five testable propositions and develops econometric models to explore how digital financial inclusion influences high-quality economic development at the county level, as well as its associated spatial spillover effects—a topic that remains underexplored in the current literature. The main scientific contributions are threefold. First, digital inclusive finance is found to significantly enhance the quality of county-level economic development, although this positive effect is subject to diminishing marginal returns. Second, upgrading the industrial structure acts as a key mediating mechanism, whereas expanding income inequality between urban and rural areas weakens the beneficial impact. Third, the spatial econometric results point to a significantly positive spatial interdependence. Interestingly, while the direct local effect of digital inclusive finance is not statistically significant, it generates substantial positive spillovers to neighboring counties—a multiplier effect that adds new insights to the spatial economics literature. In terms of policy implications, these findings advocate not only for the establishment of inter-county cooperation mechanisms in digital finance but also for the adoption of regionally tailored development strategies and stronger integration between digital inclusive financial services and local specialized industries. It should be noted that these results are derived from the context of Jiangsu Province and are intended to serve as a reference for similar regional studies.