This paper reports the findings of a study on the effects of corporate social responsibility–brand fit (CSR-brand fit) on service brand loyalty via brand identification in a brand coffee shop industry. The authors also examine how customer participation in a firm’s CSR activities strengthens the formation of service brand loyalty. Using structural equation analysis, the proposed model was tested with 237 actual customers of brand coffee shops. The results indicate that CSR-brand fit strengthens both personal and social brand identification, which in turn increase consumers’ service brand loyalty. The results also indicate that personal identification has a larger influence on service brand loyalty than social identification does. The greater effect for personal versus social identification occurs when customers participate in companies’ CSR activities. This study deepens our understanding of the link between CSR-brand fit and loyalty via personal and social identification. The research is also the first to examine how customers’ active participation in CSR activities influences the process of loyalty formation.