PurposeThe purpose of this study is to address the surging reliance on influencer marketing in evolving business models, focusing on a novel approach – the influencer e-commerce storefront. This study investigates various influencer advertising disclosures, social media activities and their impact on consumer engagement and sales within the influencer e-commerce storefront.Design/methodology/approachSecondary data was collected on 734 influencers from an e-commerce website based on “influencer” storefronts, and the influencer’s social media activity and content were collected from Instagram. Two-stage seemingly unrelated regression model was used to examine the research model.FindingsInfluencer social media use, encompassing daily posts, story posts and average comments, positively influences consumer engagement and sales on influencer e-commerce storefronts. Notably, the study reveals that different advertising disclosure languages yield varying effects. Unclear disclosures (e.g. branded Highlights) positively impact engagement and sales, while obvious disclosures (e.g. “Sponsored Ad”) negatively affect both.Originality/valueThe study contributes to Persuasion Knowledge Theory, examining influencer e-commerce storefronts and revealing the persuasive impact of undisclosed language in advertising. This study innovatively explores the effects of obvious and undisclosed sponsorship on coping mechanisms, offering insights into consumer reactions. The recommended use of undisclosed language suggests that ambiguity can enhance ad persuasion, guiding practitioners in crafting more effective messages. Moreover, the study extends co-creation theory and service-dominant logic by underscoring the significance of influencers’ social media engagement in co-creating value for consumers. Influencers’ active engagement on social media fosters co-creation, strengthening connections and boosting consumer loyalty.