Single and bilayer ceramic membranes with deposited γ-Al2O3 and Fe-SiO2 nanofiltration (NF) layers were fabricated and evaluated with respect to physical characteristics and salt removal properties. The fabrication method proved to be generally reproducible, and would be further improved controlling relative humidity during the coating process. The thickness of the individual NF layers was found to be dependent on the slipcasting of the γ-Al2O3 and Fe-SiO2 materials, regulated by the amount of water in the pores at the time of coating. Layer thickness was determined by scanning electron microscopy and measurements were compared with calculated values from nitrogen gas permeation experiments. The γ-Al2O3 material had an average pore diameter of 39Å or 43Å, depending on the firing temperature (400 or 500°C, respectively) used to sinter the NF layer to the support; the average pore diameter for Fe-SiO2 was 21Å. Porosity of the two materials was found to be 31% for Fe-SiO2 and 51% (400°C) or 42% (500°C) for γ-Al2O3. The MWCOs for rejection of polyethylene glycol were 300 g mol-1 and 700 g mol-1 for Fe-SiO2 and γ-Al2O3, respectively. Rejection of charged solutes with the membranes was correlated, in a semi-quantitative manner, with the value for potential in the center of the pore, as calculated from zeta potential measurements of the two materials exposed to various electrolytes and solution conditions. Comparisons between single layer membranes with either Fe-SiO2 or γ-Al2O3 NF layers and bilayer membranes composed of both materials showed that rejection of salts is highly dependent on solution conditions and the type of electrolyte. For NaCl, a Fe-SiO2 single layer membrane provides the largest rejection in the range of pH 5.0 to 9.0. A bilayer membrane with the γ-Al2O3 layer facing the feed solution shows superior performance for rejection of MgCl2 in the same pH range. In general, results demonstrate that the order in which NF layers are deposited on a porous ceramic support affects rejection; the layer facing the feed solution primarily controls salt removal properties. Bilayer membranes excel in salt separation, with a Cl-/SO42- selectivity four times greater than that obtained with a single layer membrane.