The effect of ligand type and the aging of the solution in the transport of trivalent chromium through Nafion 450 ion-exchange membranes was studied. Chromium chloride and sulfate solutions were employed in order to evaluate the transport number and the percent extraction of trivalent chromium ions. Results showed that the aging of the solution has a significant influence in the transport of chromium ions through the membrane, which is attributed to the changes observed in the chromium complexes due to the characteristic ligand exchange reactions. Higher values for the chromium transport parameters were obtained for chloride solutions.