This study examines whether community social capital in US counties, as captured by strength of civic norms and density of social networks in the counties, affects corporate social responsibility (CSR) of resident corporations headquartered in the counties. Analyses of longitudinal data from 3688 unique US firms between 1997 and 2009 provide strong empirical support for the propositions that community social capital facilitates positive CSR activities that benefit non-shareholder stakeholders and constrains negative CSR activities that are detrimental to non-shareholder stakeholders. Additionally, we explore the effects of institutional logics arising from community isomorphism on positive and negative CSR activities, respectively. And, we explore the respective effects of corporate engagement in positive and negative CSR activities on corporate financial performance. Firms undertake more positive CSR activities when such activities are more prevalent among other local corporations headquartered in the same county. But, there is no systematic relationship between negative CSR activities and the community-level corporate engagement in negative CSR activities. Positive CSR activities enhance a firm’s future financial performance, and the positive effect is more prominent among firms headquartered in counties with high community social capital. However, negative CSR activities only reduce a firm’s future financial performance among firms headquartered in counties with high community social capital; negative CSR activities do not affect performance among firms headquartered in counties with lower levels of community social capital. Collectively, these results highlight the distinct effects of local social institutions, namely community social capital, on positive CSR activities and negative CSR activities, respectively.