The paper presents a new method of non-linear electrochemical impedance spectroscopy (NLEIS), which allows fast and non-destructive evaluation of the corrosion rate and determination of the Tafel coefficients values for a corrosion system under investigation. This method employs amplitude modulation of the ac perturbation signal. The study demonstrated that it was possible to obtain impedance characteristic as a function of the perturbation signal amplitude based only on a single measurement. The investigations were carried out on carbon steel exposed to 1M KCl solution, which is a model corrosion system with cathodic control. The values of corrosion current and Tafel coefficients values for the corrosion reaction were determined using the dependence between the charge transfer resistance and the amplitude of the perturbation signal. (C) 2019 The Electrochemical Society.