<p>The global concern over the environmental impact of conventional plastics and the increasing accumulation of agricultural waste has driven the search for sustainable alternatives such as bioplastics. This review examines the potential of keratin-based bioplastics derived from agro-waste materials like wool and chicken feathers as a promising solution to lessen plastic pollution and valorize agricultural by-products bio-waste. This paper provides a comprehensive overview of the historical development and the classification of bioplastic based on their origin and biodegradability. Various keratin extraction techniques, including chemical hydrolysis and dissolution using ionic liquids, are critically compared. Recent advancement in enhancing keratin-based bioplastic through the use of plasticisers, crosslinkers, fillers, and physical treatments are discussed. This review also address the challenges related to public acceptance, legal frameworks, environmental implications, scalability and mechanical limitations. While keratin-based bioplastic offer a viable pathway toward a bio-based and circular economy, their broad use will require further research, technological innovation, and supportive policy frameworks.</p><p>The environmental burden of conventional plastics and the accumulation of agricultural waste have intensified efforts to identify sustainable material alternatives. This review critically evaluates the potential of keratin-based bioplastics derived from agro-industrial waste, such as poultry feathers and wool, as a strategy to simultaneously mitigate plastic pollution and valorise underutilized waste streams. A comparative analysis with established bioplastics, including polylactic acid (PLA), polyhydroxyalkanoates (PHAs), starch-based and cellulose-based materials, highlights that keratin offers distinct advantages in feedstock circularity and biodegradability but remains limited by processing maturity, mechanical performance and moisture sensitivity.</p><p>The influence of extraction methods on keratin structure and downstream material properties is critically examined, with conventional chemical approaches, biological treatments and ionic liquid–based systems evaluated in terms of efficiency, environmental impact and scalability. While conventional methods offer simplicity and scalability, they often compromise protein integrity, whereas emerging techniques provide improved structural preservation at higher cost and complexity.</p><p>Strategies for enhancing keratin-based bioplastics, including plasticisation, crosslinking and composite formulation, are discussed as critical levers for improving mechanical and functional performance. However, these modifications introduce additional constraints related to processing complexity and end-of-life behaviour. Overall, keratin-based bioplastics are unlikely to completely replace established materials in high-volume commodity markets in the near term, but they show strong potential for niche and high-value applications where waste valorization and specific functional attributes are prioritized. Future progress will depend on advances in scalable and greener extraction technologies, integrated material design and comprehensive techno-economic and life cycle assessments to support industrial implementation.</p> Graphical abstract <p></p>