This study examines interactions between customers and organisations on social media by investigating how user-generated content influences interactions between organisations and customers on social media. In compliance with existing perspectives on user-generated content, a total of seven independent determinants of online interaction were taken into consideration including content type, information richness, message direction, content valence, type of message, message length and the use of punctuation marks. The findings show that user-generated content on social media contains multiple elements and dimensions that influence interactions between customers and organisations. The user-generated content posts that triggered the most interactions typically included content that is visual, personal, and attractive. The findings furthermore indicate that it is important for organisations to be recognisable on social media, creative with content and loyal to active fans. Moreover, this paper shows that organisations should not use Facebook as a marketing tool, but as an engagement-building communication tool.