This study deals with the preparation and characterization of thermoplastic composites using polypropylene, high-density polyethylene and polylactic acid matrices and including whole chicken feathers as reinforcement. The behaviour of the composites was determined in terms of physical and mechanical properties, which were related to the fibre–matrix compatibility analysed by Fourier transform infrared spectroscopy and scanning electron microscopy. The results showed that the addition of chicken feathers into the thermoplastic matrices results in a slight increase in the stiffness when small amounts of chicken feathers (5–10% vol/vol) were incorporated into the composites. Tensile strength at maximum load, elongation at break and toughness properties decreased when the chicken feather concentration was increased. Results for chicken feather–polypropylene composites were analogous to chicken feather–high-density polyethylene and chicken feather–polylactic acid composites. The Fourier transform infrared spectroscopic study and the scanning electron micrographs suggest that the insufficient compatibility of chicken feather and polymer matrices is the main reason for the decrease in tensile properties