The skin microbiome comprises a diverse community of bacteria, fungi, and archaea, all of which play a foundational role in maintaining skin health, immune tolerance, and barrier integrity. Recent advances in cosmetic science focus on the skin microbiome through the incorporation of prebiotics, probiotics and postbiotics in topical skincare formulations. This review critically examines the scientific understanding of the skin microbiome, explores the mechanisms and extractions of key “biotics” ingredients, and evaluates the clinical and regulatory landscape surrounding their use in the cosmetic industry. Despite promising scientific data and early clinical findings, there are notable challenges, including limited robust in vivo evidence, regulatory ambiguity, difficulties in formulation, and inconsistent definition and marketing claims. Regulatory harmonisation and the development of standardised testing protocols are necessary to fill the gap in today’s research and to maximise the benefits of “biotics” in the cosmetic industry.