Digital finance development level and corporate debt financing cost

•Digital finance can reduce the cost of corporate debt financing.•Digital finance's impact on corporate debt's cost is regionally heterogeneous.•The impact of digital finance on the cost of corporate debt is industry heterogeneous. This paper selects the data of China's A-share listed companies from 2012 to 2022 as the research object to explore the impact of digital finance on the cost of corporate debt financing. It is found that the development of digital finance can significantly reduce the cost of corporate debt financing; the impact of digital finance on the cost of corporate debt financing has regional heterogeneity, and the impact of digital finance on the cost of corporate debt financing has industry heterogeneity.