Liquid-quenched metallic amorphous alloys (FeCo)75(SiB) have been studied by 57Fe Mössbauer spectroscopy at room temperature. Direct insight in the short-range order (SRO) and the bonding properties involving Fe atoms in these alloys is presented, taking apart clearly the metal and metalloid influence over such properties. A large increase of the SRO is found in the Co-rich alloys which is also affected by variations in the relative concentration of metalloids Si and B. Such SRO changes influence the bonding of Si and B with Fe. The substitution of B for Si decreases the Fe 3d polarization in the Co-rich alloys with large SRO.