China's wide-ranging circular economy (CE) efforts have been studied multiple times from a range of perspectives. Synthesizing the relevant literature, this paper provides a critical reflection on the transition to a CE in China. Key factors for China's success in shifting towards a CE are seen in multi-level indicators and upscaling niches. This paper makes a novel contribution on limitations to progress, based on emerging evidence on CE projects that fail to sustain. Enriched by experts feedback, this paper critically addresses future challenges to a deep transition resulting from implementation gaps between early majorities and mass markets and coordination challenges arising through regional and sectoral differences. In light of China's commitments to climate neutrality by 2060, such challenges are considered serious. Based on feasible policy learning, the paper however proposes synergies between the CE and decarbonisation driven by efficiency improvements, comprehensive core indicators, upscaling and urban policies as trigger for deeper transformations. Finally the paper undertakes broader reflections and an outlook on evidence-orientated policy learning for a CE and decarbonisation in China.