The etching of the soft magnetic CoNbZr alloy in aqueous HF-free solutions containing H2O2 was investigated. The influence of solution composition, temperature, and Nb content of the alloy on the etch rate was studied. X-ray photoelectron spectroscopy analyses were performed to examine the surface composition during etching. Patterns with an excellent edge definition were obtained. The etching process was isotropic in nature, but beveled edges could be obtained due to an Nb-poor surface film.