FeCo alloy nanoparticles, exhibiting a high degree of stability against oxidation in ambient conditions and thermal stability up to 300 °C, have been synthesized by a simple and cost-effective polyol process. X-ray diffraction measurements confirm the formation of FeCo with no other impurities. Electron microscopy reveals spherical morphology of the particles with uniform size distribution. Bulk magnetic measurements confirm soft nature of the alloy nanoparticles, with a high saturation magnetization ~ 195 emu/g, which remains intact up to a 6-month test period. Thermogravimetric analysis performed in air also suggests the stability of these magnetic nanoparticles up to 300 °C. Mossbauer spectroscopy further confirms alloy formation and indicates the presence of an additional non-magnetic component, the latter being responsible for the stability of these nanoparticles in air.