Although most consumers are positive about socially responsible companies, in order to benefit from CSR efforts, effective and clear CSR communication is important. However, due to the constantly rising profusion of eco-labels, based on either own claims from the organization or claims made by an external third party, consumers may encounter difficulties in identifying truly responsible firms, which could result in less effective CSR initiatives, even for those responsible firms. Therefore, building on attribution theory, this study seeks to identify how uncertified internal CSR claims and external third-party CSR labels should be used in order to deter greenwashing and increase positive consumer evaluations. Within a 3 (external third-party CSR label: positive vs. negative vs. no label) × 2 (uncertified internal CSR claim: present vs. absent) design, respondents are exposed to different coffee product packages measuring their attitude toward the brand, corporate credibility, purchase intention, and scent perception, as well as perceived attributional CSR motives. Overall, findings indicate that especially an external CSR label affects consumer responses toward the firm. Moreover, perceived CSR motives serve as a mediator between an external CSR label and corporate credibility and brand attitude, respectively. These findings warrant further consideration of introducing an external multilevel rating systems by governmental law.