The rapid growth of social media has transformed how tourists create and disseminate travel experiences, making user-generated content a critical driver of destination image and decision-making. This study develops an integrated framework grounded in self-determination theory and personality theory to investigate how intrinsic motivations (perceived enjoyment, documentation, and altruism) and extrinsic motivations (recognition and status, and social interaction) influence tourists’ intention to share travel experiences on social media, with extraversion as a moderating variable. A quantitative approach was employed using survey data, and the proposed relationships were tested partial least squares structural equation modeling (PLS-SEM). The results reveal that all motivational factors exert significant positive effects on sharing intention. Perceived enjoyment emerges as a particularly strong predictor, underscoring the importance of affective experience, while documentation highlights the role of content creation in facilitating sharing behavior. Altruism confirms the prosocial nature of sharing, whereas recognition and social interaction emphasize the importance of social approval and interpersonal engagement. Furthermore, extraversion significantly moderates most of these relationships, indicating that individuals with higher levels of extraversion are more likely to translate motivations into sharing intentions. However, the absence of a moderating effect in the documentation–intention relationship suggests the existence of boundary conditions in the influence of personality traits. The study contributes theoretically by advancing an integrative understanding of sharing behavior that incorporates both motivational and personality-based mechanisms. Practically, the findings provide actionable insights for destination marketers in designing strategies to stimulate user-generated content by leveraging experiential value and tailoring engagement approaches to different personality profiles.