Social networks are a driving force of digital transformation and offer firms the opportunity to market products and services to both international consumers and providers, establish durable relationships with them, and improve their own competitiveness. The study analyzes the role played by the use of Facebook for online advertising, building interaction and brand communities, implementing social CRM activities, and conducting market research, as well as a sales channel alternative to physical presence, in firms’ international export performance, both in terms of managers’ perceptions and Facebook buy button conversion rate. A survey-based empirical analysis of 105 fashion firms operating worldwide was conducted. The results of multiple regression analyses show that building conversations and brand communities positively affects international export performance, while advertising via Facebook yields mixed results. By comparing firms that have a physical presence with those that do not, the former turned out to benefit from especially in-store advertising and promotions to enhance their Facebook buy button conversion rate; while the latter can improve their performance mainly by adopting outdoor and transit advertising and digital marketing. The research contributes to the existing body of knowledge on social media marketing and international business and, by adopting a firm-level perspective, provides interesting insights for practitioners since it allows to understand how to develop an effective Facebook strategy to succeed in foreign markets.