Can Low-Carbon Policy Enhance Green Total Factor Productivity of Manufacturing Enterprises? Evidence from China’s Low-Carbon City Pilot Policy

China’s Low-Carbon City Pilot (LCCP) policy aims to drive green economic transformation, but its firm-level effects on manufacturing are underexplored. This study takes the LCCP policy as a quasi-natural experiment and employs a staggered difference-in-differences (DID) model to examine its impact on manufacturing enterprises’ green total factor productivity (GTFP). The findings are fourfold. (1) The LCCP policy significantly enhances manufacturing enterprises’ GTFP, a conclusion that has been validated through multiple robustness tests. (2) Green technological innovation and financing constraint mitigation serve as two key mediating channels. (3) Enterprise market power exerts a negative moderating effect. (4) The promotional effect of the LCCP policy on GTFP is more pronounced among manufacturing enterprises with a high degree of equity balance, state-owned enterprises, and heavily polluting enterprises. This paper offers empirical evidence and policy implications for how governments can effectively exert their guiding roles and how manufacturing enterprises can achieve a win-win outcome for both economic and environmental performance.