Inefficient energy pricing hinders economic development in many countries. We examine longrun effects of a recent heating reform in China that replaced a commonly-used fixed-payment system with individually-metered pricing. Using staggered policy rollouts and administrative data on household-level daily heating consumption, we find that the reform induced long-run reductions in heating usage and generated substantial welfare gains. Consumers gradually learned how to conserve heating effectively, making short-run evaluations underestimate the policy impacts. Our results suggest that energy price reform is an effective way to improve allocative efficiency and air quality in developing countries, where unmetered-inefficient pricing is still ubiquitous.