A method for making a Fe-based soft magnetic alloy where an alloy melt is injected onto a moving cooling unit to form an amorphous alloy ribbon. The alloy melt contains Fe as a main component, B and at least one metallic element M selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Mo and W, the composition of the alloy melt being selected such that the resulting amorphous alloy ribbon is characterized by a first crystallization temperature at which fine grain bcc Fe crystallites precipitate, and a second crystallization temperature at which a compound phase containing Fe--B and/or Fe--M precipitates. The amorphous alloy ribbon is then annealed at a temperature which is higher that the first crystallization temperature and less than the second crystallization temperature for an annealing time in the range of 0 minutes to 20 minutes.