The purpose of the present work was for identify limits for the formation of stable polyelectrolyte multilayers (PEMs) from cationic and anionic starches (with degrees of substitution of 0.04-0.09) on SiO2 surfaces, taking account of the effect of the charge density of the starches and the salt concentration in the surrounding water phase. The experiments were performed at a pH of 6.3 using stagnation point adsorption reflectometry (SPAR) and quartz crystal microbalance with dissipation (QCM-D). From these experiments it was concluded that it is possible to form PEMs by the adsorption of oppositely charged starches on SiO2 surfaces; it was also found that adsorption of the first layer is controlled both by electrostatic, non-ionic interactions and by pure steric restrictions, i.e. geometrical restrictions, at the surface. The results also indicate that the charge density of the starch must exceed a certain value to allow multilayer formation and that this critical charge density increases with increasing salt concentration. The combination of charge densities of the cationic/anionic starches was also found to influence the adsorption behaviour, and the formed polyelectrolyte multilayers had a high water content of 69-92%. © 2010 WILEY-VCH Verlag GmbH & Co.KGaA, Weinheim.