The influence of low-temperature annealing on the magnetic hysteresis loop parameters of magnetostrictive Co-Si-B and nonmagnetostrictive Co-Fe-Si-B glasses was studied. The dependence of Curie temperature ( T C ), crystallization temperature ( T x), full-stress-relaxation temperature, saturation magnetostriction constant, saturation magnetization and coercive field H c on metalloids contents for as quenched Co 100- x (Si 0.5B 0.5) x glasses was determined. It was found that annealing enhances remanence magnetization for all investigated Co-Si-B glasses. The coercive field of these glasses is influenced by annealing owing to: stress relaxation (resulting in an H c decrease) and domain structure stabilization (resulting in an H c increase). Significant H c reduction for both magnetostrictive and non-magnetostrictive glasses was observed, after annealing above T C . For glasses with T C <> T x , it was necessary to apply an external magnetic field in ord er to decrease H c. It was found that non-magnetostrictive metallic glasses with low Curie temperatures ( T C ⪷ 450 K) exhibit the most stable magnetic hysteresis loop parameters.