 This study investigates the potential of using waste iron filings, WIFs, as a filler material in glass fiber reinforced epoxy, GFRE, composites. The results show that WIFs can increase the density, surface hardness, Young's modulus, and tensile strength of the GFRE composites. However, the addition of more WIFs leads to lower elongation at break and electrical conductivity. This suggests that WIFs are not suitable for all applications, but they may be useful for certain applications such as structural dynamic monitoring systems in the construction industry. Additionally, the use of WIFs supports the effort toward a circular economy.