PurposeEffectiveness of message tactics in social marketing projects often varies across groups of individuals, which suggests the importance of tailoring communication approaches to maximize the success of promotional strategies. This study aims to contribute in this direction by using an innovative approach to promote targeted human papillomavirus vaccination, applying conjoint analysis to understand parental preferences for social media content features.Design/methodology/approachAn online purpose-built quantitative survey was administered to a group of parents meeting eligibility criteria. The survey questions were designed based on inputs from formative qualitative research conducted in a previous phase of the study.FindingsIn the overall sample of 285 parents, responses show that image was the most important feature of social media posts overall, followed by source and text. Cluster analysis identified eight segments in the sample based on parental preferences for content features. Significant differences across segments were identified in terms of need for cognition, vaccine hesitancy, parental gender, concerns around side effects, trust in medical providers, information sharing behaviors on social media and information seeking online.Originality/valueThe application of conjoint analysis to promotional content allows to assess which features of the content are most important in persuading different individuals and provide insights on how people process the information, ultimately to inform targeted promotion based on preferences. Conjoint analysis has been widely used in consumer research to explore audience preferences for products or services, but only a few applications of conjoint analysis to the design and testing of promotional content are found in the literature.