A low-cost Fe 80 P 11 C 9 bulk metallic glass (BMG) was developed with excellent soft-magnetic and mechanical properties (compressive strength: 3.2GPa; plasticity: ∼1.4%). The partially devitrified alloy with α-Fe nanophase (3–5nm) obtained using an isothermal kinetics method shows further improvement of soft-magnetic properties with magnetic polarization of 1.49T, coercivity of ∼4Am −1 and effective permeability of 11,000 at 1kHz. The alloy is a promising model material for studying the structural and functional properties of ferromagnetic BMGs.