The charge densities of acrylamide/acrylate copolymers can be determined using tensammetry. The tensammograms were run using 20 ppm solutions of polymer in 0.1 Mtetraethylammonium chloride. A standard curve of desorption peak height versus mol% anionicity was useful in the range 10–50%. A second standard curve of the potential at which the capacitive current measured 1 μA versus mol% anionicity allowed the determination of charge density in the range 0–15%.Keywords: tensammetry, polyaerylamide, charge density, tetraethylammonium, desortion peaks.