Unidirectional hybrid FRP composites containing moderate strength carbon fibre (CF) and E-glass fibre (GF) arranged in different stacking configurations and hybrid rations, i.e. rh = VfG/VfC were produced, tested and analysed. Span-to-depth ratios of 16, 32 and 64 were employed for the three-point bending test in accordance with the ASTM D790-07 standard. After being loaded to failure, regions close to the fracture areas were removed from the broken specimens, casted into polyester block, polished, and their micrographs captured using an optical microscope. No influence of span-to-depth ratio was noted on the failure modes, unlike that noted in previous work. The majority of the specimens were failed by either in-plane or out-of-plane local buckling followed by splitting at the compressive GFRP side and matrix cracking combined with fibre breakage in the CFRP tensile face. Additional specimens also exhibited inter-layer delamination due to the presence of matrix-rich region between adjacent prepreg layers, suggesting that the failure mode may have been mainly affected by the manufacturing procedure and microstructure rather than span-to-depth ratio.