The propagation of arsenous acid−iodate reaction fronts of different net stoichiometries in externally applied dc electric fields is studied for a range of both electric field intensities and initial compositions of the reacting mixture (represented by the stoichiometric factor S 0). Regions of three different types of net stoichiometry in the parametric space ℰ/V vs S 0, where ℰ is the intensity of the applied electric field and V the reaction front propagation velocity, are determined both experimentally and by analyzing a reaction−diffusion−migration model that includes a realistic kinetic scheme of the reaction studied. Both agreement with and discrepancies between the theoretical predictions and experimental findings are discussed.