Purpose – This paper explores how companies can improve consumer attitudes towards corporate social responsibility (CSR) messages and companies by designing the content of the message, which should provide specific information and improve social topic awareness among consumers. The paper also explores the mediating role of message authenticity between the CSR message content and consumer attitudes towards the information and the company. Design/methodology/approach – 302 participants evaluated the website of a fictitious company that included information about its CSR activities. The authors collected data through a questionnaire of Likert-type and dichotomous scales and contrasted the hypotheses with a causal model, analysing the relationships among variables through structural equation modelling (SEM) with the software EQS 6.1. Findings – The findings suggest that information specificity and social topic awareness improve consumer perceptions of message authenticity. The findings also show that message authenticity improves consumer trust and attitudes towards the information and the company. Attitude towards the information, message authenticity and social topic awareness show the largest impacts on trust and attitude towards the company, while information specificity also has a positive although smaller effect. Originality/value – Integrating information specificity and social topic awareness within the conceptual model presented in this paper, based on the heuristic-systematic model (HSM) and attribution theory, allows researchers and practitioners to close the gap between companies’ CSR activities and consumers’ perceptions, attitudes and behaviours.