Production of composites from recycled materials plays a significant role in the circular economy model, transforming waste into new products with added value. This study evaluates the mechanical properties of polymeric composites based on recycled high-density polyethylene (HDPE). The research considers manufacturing methods through thermal pressing and extrusion, allowing a technological comparison between these techniques. Four concentrations (0%, 5%, 10%, and 15%) and two particle sizes (60 and 100 mesh) of charcoal incorporation into the HDPE matrix were evaluated to investigate how the addition of this material affects the physical properties of the composites. The results demonstrate that the material obtained through the pressing method, with the incorporation of fine particles of 60 mesh size, exhibited an average static modulus of elasticity (MOE) of 287.14 MPa, a higher value than that observed in composites produced by the thermal pressing method with 100 mesh particles, which recorded an average MOE of 245.80 MPa. In contrast, in the extrusion process, the opposite trend was observed: the condition with 100 mesh particles resulted in an average MOE of 284.50 MPa, higher than that obtained with 60 mesh particles, which presented an average MOE of 254.61 MPa.