There is an ongoing discussion on the necessity of implementing disclosures for digitally manipulated pictures within the branded content of social media influencers (SMIs). To address this, we conducted two online survey-based between-subjects experiments to assess the effectiveness of digital manipulation disclosures used on Instagram by an SMI. In the first study (N = 99), we examined how a visual prominent disclosure placed directly on the sponsored posts of an SMI, mediated by the recognition of digital manipulation and the perceived authenticity of the SMI, influenced participants’ intentions toward the SMI, their brand attitude, and their likelihood in engaging in electronic Word-of-Mouth. In the second study (N = 155), we manipulated three conditions: the absence of digital manipulation, the presence of digital manipulation without disclosure, and the presence of digital manipulation with disclosure. We investigated the effects of digital manipulation on the perceived credibility of the SMI and on brand related factors, mediated by the recognition of digital manipulation. Moreover, we explored the moderating effects of product involvement on the relationship between digital manipulation recognition and source credibility. Recognizing digital manipulation has no effects on the perceived authenticity of the SMI. Among social media users with high levels of product involvement who can recognize the digital manipulation, the perceived credibility of the SMI tends to be lower. The research holds both theoretical and practical implications for the field of influencer marketing and disclosure practices.