Composite materials have distinct properties such as a high strength-to-weight ratio, high corrosion resistance, a high modulus-to-weight ratio, and wear resistance. The potential, strong mechanical properties and lower cost properties of E-glass fibre motivated us for this work. Tensile, flexural, and Izod impact tests were used in the current study to conduct a static analysis of E-glass reinforced isophthalic polyester composite and E-glass reinforced general purpose (GP) or orthophthalic polyester composite. Thermal-mechanical behaviour was investigated using thermogravimetric analysis and dynamic mechanical analysis tests. Furthermore, the surface morphology of the tested composites was examined using a scanning electron microscope. When compared to E-glass reinforced GP polyester composite, E-glass/isophthalic polyester composite demonstrated superior flexural properties and thermal stability. However, the tensile and impact properties of E-glass/GP polyester composite were found to be higher than those of E-glass/isophthalic polyester composite. SEM images show fibre pull-out, matrix cracking, and fibre breakage, among other things. The loss modulus and damping values for E-glass reinforced GP polyester composite were found to be greater than those for E-glass reinforced isophthalic polyester composite. The current composite can be used in marine applications, particularly the hull: frame or body of the boat.