The COVID-19 crisis has precipitated the largest decline of global greenhouse gas (GHG) emissions on record. Those massive current declines are likely temporary, but they raise important questions about the trajectory of emissions as the economic crisis abates and economic activity resumes. Given the increasing importance of “bottom-up” action on climate, this analysis inventories the various GHG reduction pledges and commitments of the 100 largest U.S. cities; estimates the emissions savings that could result from those pledges; and then evaluates whether U.S. cities appear to be on track to meet their pledges. In this fashion, the information addresses the current array of results on the ground in order to inform ongoing discussions of the potential and limits of “bottom-up” climate strategies in the COVID era.