The adsorption of proteins to ion exchangers was investigated by finite bath experiments and by computer simulations using existing rate models. Experimental data were obtained for the binding of bovine serum albumin at different feed concentrations to both cation and anion exchangers. The results were interpreted together with model predictions and the values of the parameters characterizing the mass transfer mechanisms as well as the interaction rates of the adsorbate-adsorbent complex were estimated. The best agreement between theory and experiment throughout the whole period of adsorption process was obtained with a complex model where several steps of the overall mechanism were simultaneously controlling the overall rate. The simplified models, which offer rapid solution requiring less computational power, can be used at low feed concentrations of the proteins where the mechanisms controlling the adsorption rate are less complex. As the interaction rate mechanism and the intraparticle mass transfer mechanism in the adsorbent particles are the same in both finite bath and column adsorption systems, the information presented in this paper can be used to predict the protein adsorption in a column chromatography system.