In the past few years, online social networks (OSNs) have become among the most frequently visited sites on the Internet. Consumers rely on other users’ comments and reviews prior to purchasing products and services; therefore, the role of OSNs in consumers’ decision-making process has become an important marketing phenomenon. Contemporary companies are trying to create online communities and engage users to post positive word of mouth (WOM) in OSNs and build long-lasting relationships with consumers. A review of the literature underlines the role of satisfaction and trust in customer–company relationships. This study examines the relationships between trust, satisfaction, behavioral intentions, and WOM in the OSN context. An online questionnaire was deployed and a structural equation model was implemented to test a theory-driven model. Findings indicate that trust is a vital component for OSN marketing. In online environments, trust tends to have a positive influence on satisfaction, and satisfaction partially mediates the impact of trust on brand behavioral intentions and WOM.