As nations agreed on a bottom-up approach to establish the Paris Agreement in 2015, Non-state Actors (NSAs) became increasingly acknowledged as key players in the implementation of Nationally Determined Contributions (NDCs). In a mostly urbanised world, local governments have a major part to play in designing and implementing climate policies that will help overcome carbon lock-in and enable the transition to a sustainable lowcarbon future. Transnational municipal networks (TMNs) have a well-documented history of contributing to multilevel climate governance and supporting experiments in local climate action in many countries. In Brazil, urban climate experimentation has increased since 2005 and accelerated after 2015. Based on empirical evidence from a national survey and two Brazilian metropolises, the study demonstrates that TMNs have been drivers of the municipal climate agenda in Brazil, but there is no evidence so far that urban governance experiments have resulted in significant greenhouse gas emission reductions. Furthermore, the collective impact of cities' experimentation on the national climate agenda is yet to be verified. In light of multilevel climate governance and the urban experimentation conceptual framework, we contend that while there is no documented evidence that local climate action has affected Brazil's ability to meet its mitigation goals, cities' paradiplomacy and policy experiments have strengthened a multilevel approach to climate governance and contributed to positive change towards a sustainable transition. Furthermore, a closer look at policies across scales and their interactions will help our understanding of how to improve t'he institutional framework for climate governance in Brazil and secure GHG emission reductions, thus contributing to global goals beyond 2020.