In the current era, numerous human-like virtual influencers (VI) on social media promote brands without immediately revealing their non-human nature, intending for viewers to realize it later. This marketing strategy raises a question regarding their endorsement effectiveness. Grounded in Computers are Social Actors (CASA) paradigm, this online experiment employs a quota sample of Korean adults (N = 128) to explore how the timing of VI identity disclosure (before vs. after exposure to sponsored content) affects viewers' attitudes toward the VI and, subsequently, their intentions to purchase the endorsed brand or spread word-of-mouth. Additionally, based on the match-up hypothesis, this study examines how perceived influencer-brand fit impacts these relationships. Moderated mediation analyses reveal that viewer attitudes mediate the relationship between disclosure timing and behavioral intentions, with VI-brand fit significantly moderating this mediation. The findings underscore the negative effects of delayed VI identity disclosure and emphasize the critical importance of a strong influencer-brand match.
