Why are China’s notoriously competitive local governments increasingly cooperating with each other? Combining interjurisdictional cooperation data from 820 counties and fieldwork in 24 localities, we argue that the increasing trend of inter-county cooperation is the newest manifestation of China’s state-rescaling initiative. It is the combined result of the state’s devolution of governance responsibilities and competitive-minded local cadres’ interests in benefits associated with scaling up. The study contributes to understanding how counties’ growing interdependence intersects with the regime’s survival logic in the unfolding reconfiguration of China’s counties.