Recently a new theory of toner adhesion was suggested. In this new theory an electrostatic proximity force of adhesion is taken into account. The proximity force is due to the attraction of charges on the toner particle in close proximity to a conductive plane to their respective image charges in the conductive plane. In this paper experimental verification of this new theory is presented using a 16 μm diameter, ground toner with silica additives. The theory is fit to complete curves of the developed and residual (1) mass per unit area, (2) charge-to-mass ratio, and (3) size distribution in an electric field detachment experiment, a much more stringent test of an adhesion theory than has been published before (to the authors' knowledge). The observed adhesion and ratio of the measured toner adhesion to theory are the lowest ever observed (to the authors' knowledge).