["Journal of Consumer Behaviour, Volume 25, Issue 2, Page 676-702, March 2026. ", "\nABSTRACT\nSustainable fashion is both a growing consumer trend and an urgent societal imperative, yet the use of virtual influencers to promote sustainable fashion raises concerns about authenticity and greenwashing. This research examines whether hybrid influencers—virtual influencers paired with human companions—can enhance the persuasiveness of sustainability communication. Study 1, a qualitative exploration (21 interviews), identified three key pro‐environmental behavior themes: sustainability awareness, sustainable practices, and environmental citizenship (e.g., advocating green fashion within social networks). Interview data also reveal distinct perceived strengths of each influencer type (e.g., genuineness in human influencers, consistent engagement in virtual influencers, and relatability and trustworthiness in hybrid influencers). Building on these insights and prior literature, we propose a conceptual framework explaining how influencer type and message framing shape sustainable fashion intentions. Two subsequent experiments (Study 2, N = 234; Study 3, N = 457) confirmed that hybrid influencers were more effective than virtual‐only influencers in promoting sustainable fashion intentions. Moreover, message valence moderated this effect; negative message framing was especially persuasive when delivered by hybrid influencers. Across studies, wishful identification emerged as the key mediator, while anthropomorphism was ruled out as a mediator, highlighting the limitation of anthropomorphism in the sustainability messaging context. Together, these findings advance theory on virtual influencers and sustainability communication and offer practical guidance for brands and nonprofits seeking to authentically engage next‐generation fashion consumers.\n"]