This study builds on previous research on information technology implementation and usage in small and medium-sized enterprises (SMEs) and applies a special focus on social networks. Specifically, this research investigates antecedents of social network usage in SMEs and respective performance outcomes. The results show that entrepreneurial orientation is positively related to social network usage in SMEs, whereas responsive market orientation shows no effect. Social network usage is not directly related to SME growth; yet it mediates the relationship between entrepreneurial orientation and SME growth. Interestingly, large firms show the opposite effects regarding antecedents and performance-related consequences of social network usage.