• All three influence tactics (internalization, compliance, ingratiation) positively impact message sharing. • Ingratiation tactic has the strongest effect on brand message sharing. • Consistency or variation in the use of influence tactics across tweets enhances sharing. • Aligning influence tactics with brand name gender (e.g., ingratiation for feminine brands) improves sharing effectiveness. Brand message sharing is a crucial outcome of social media marketing. This research draws on the conceptual framework of influence tactics to provide insights into how specific tactics—internalization (e.g., offering objective information), compliance (e.g., exerting demands), and ingratiation (e.g., expressing emotions)— embedded in brand communications impact brand message sharing. By developing a machine learning model, this study analyzes a dataset of 893,054 brand-related tweets from 122 S&P 500 brands and demonstrates that these three influence tactics significantly enhance brand message sharing. In particular, ingratiation exerts a stronger influence on brand message sharing compared to internalization and compliance. Moreover, a high level of consistency or a high level of variation in the influence tactics used in sequences of posted messages boosts brand message sharing. Additionally, tailoring ingratiation and compliance tactics to feminine and masculine brand names, respectively, can further enhance the effectiveness of brand message sharing.