With the growing importance of CSR, more fashion brands have actively engaged in CSR activities, and consumers’ perception of their motives has become a critical issue. This study investigates the influence of perceived CSR motives on fashion consumers’ perceived sincerity, trust, and behavioral intentions. In addition, the effect of ‘CSR timing’ and ‘information source’ on these variables was examined. In a 2x2 between- subjects design with scenarios, 515 adult consumers responded to an online survey questionnaire. The study identified three CSR motives: value-driven motive, instrumental motive, and strategic motive. The SEM results showed that the value-driven and instrumental motives influenced trust and behavioral intentions. In particular, perceived sincerity mediates value-driven motive and trust. A comparison of latent means revealed the effect of CSR timing on value-driven and strategic motives, trust, sincerity, and behavioral intentions. This study provides an insight into the relationship between consumers’ perception of CSR motives and their reactions, and the importance of CSR timing.