Purpose As the pace of carbon emission reduction in China slows, understanding how to reduce carbon emission inequality becomes increasingly important. However, urban-rural carbon emission inequality has received limited attention. This study aims to explore the causal relationship between smart logistics policy (SLP) and urban–rural carbon emission inequality (URCEI), and aims to provide new insights into mitigating carbon emission inequality. Design/methodology/approach Using a difference-in-differences model and a dataset comprising 32,317 observations from 2045 counties in China between 2000 and 2022, this study measures the impact of SLP on URCEI and estimates the regional moderating variables influencing this relationship. Findings The results indicate that SLP significantly mitigates URCEI. Furthermore, the study identifies rural population density, fixed asset investment, the number of employees in the scientific and technical services industry, and the number of invention patent applications as critical factors influencing this causal relationship. Originality/value This study provides new evidence on the role of SLP in mitigating URCEI and introduces regional moderating variables, offering a novel perspective for reducing URCEI.