Despite the growing importance of influencers' word‐of‐mouth through audiovisual content, little is known about its effect on consumers' brand evaluation, purchase intentions, and decisions. Drawing on Ohanian's source credibility framework, we conducted two studies across different influencers, product categories, and respondents' gender and tested the hypotheses using covariance‐based and partial least square structural equation modeling. Study 1 focuses on a mega‐influencer of cosmetic and beauty brands and predominantly involves female respondents. The findings show that the influencer's attractiveness affects perceptions about source expertise and source trustworthiness but not brand attitude, while source expertise predicts source trustworthiness, and both mediate the effect of source attractiveness on brand attitude. In contrast, brand attitude predicts purchase intention and mediates the impact of source credibility dimensions. Study 2 focuses on various influencers of hedonic products (lifestyle, fashion, and beauty). The results confirm the influence of source attractiveness and expertise on source trustworthiness, which ultimately predicts consumer purchase decisions. This study reveals the interdependencies between different source constructs, contributing to source credibility theory. Furthermore, we show that the effect of source dimensions that are relevant in the celebrity endorsement literature, such as source attractiveness, do not directly influence consumers' intentions and decisions in the context of influencers' electronic word of mouth. Finally, the two studies confirm that only influencers perceived as honest and sincere can influence consumers' purchase decisions.