Using panel data of Chinese A-share listed firms spanning 2013 to 2024, this paper investigates the statistical association between the disclosure–implementation mismatch in digital transformation and corporate ESG ratings. The disclosure–implementation mismatch is constructed as an empirical proxy capturing the divergence between firms’ digital-transformation disclosures in annual reports and their substantive digital inputs. We stress that this proxy can reflect multiple neutral sources of divergence, such as investment time lags and outsourcing arrangements, and should not be equated solely with managerial opportunism. Baseline regression results document a statistically significant negative association between this mismatch and corporate ESG ratings. Exploratory heterogeneity analyses show that such correlational pattern is more prominent among firms without Big-Four audits, firms located in high-marketisation regions, and firms with lower managerial ownership.