Most of the automobile industries use natural fiber composites for the manufacturing of components since they serve as a better choice for composites reinforced with glass. This research focuses on the usage of natural fiber composites such as Achyranthes, Aspera, and Bagasse owing to their low weight, low cost, availability, eco-friendly, and also natural fiber composites are replacements for metal matrix composites due to their high stiffness and high strength-to-weight ratio characteristics. Synthesis of various natural fiber composites using reinforcements such as Achyranthes aspera and bagasse fibers, as well as glass fibers, utilizing a polyester-based matrix resin. The characterization of mechanical properties such as hardness, impact strength, tensile strength, and flexural strength has been carried out for these materials in dry and wet conditions. And also, the thermal stability of the composite has been investigated using a heat deflection test. © 2025 Elsevier B.V., All rights reserved.