Purpose: Over the past few years, social networking sites (SNSs) have become very useful for firms, allowing companies to manage the customer-brand relationships. In this context, SNSs can be considered as a learning tool because of the brand knowledge that customers develop from these relationships. Because of the fact that knowledge in organisations is embodied in the concept of the learning organisation, customers may create brand knowledge as a consequence of two learning facilitators: informational and instrumental value. Then, the purpose of this paper is to identify the role played by brand knowledge in the process of creating customer capital, in the context of SNSs. Design/methodology/approach: A total of 259 users of SNSs, who were followers or fans of brand pages, participated in this study. Data were collected through an online survey and they were analysed using structural equation modelling. Findings: The results of the study show that brand pages at SNS can perform brand knowledge by providing purposive gratifications to its customers. Moreover, they can also develop an indirect effect on customer capital, through the direct effect that brand knowledge has on it. Therefore, the results of the study will help managers design their learning strategies in relation to SNS and confirm the need of using SNS as a learning tool. Originality/value: Few, if any, studies have analysed whether gratifications, usually related to media, work as learning facilitators in the context of brand pages at SNS.