A theoretical model for the kinetics of leveling agents in plated through-hole processes is presented. A Langmuir adsorption isotherm with a mass-transfer mechanism was assumed. The surface concentration of the leveling agents was determined at various values of two adsorption parameters, k(2) (the desorption rate constant) and K (the product of the adsorption equilibrium constant and agent bulk concentration). The current distribution in the presence of leveling agents was calculated from these parameters and locally available areas for deposition.