The adsorption of I- ions on (fie singular (111), (001) and (01 (1) over bar) planes of the bismuth single crystal from solutions in ethanol has been investigated by electrode impedance and charge measurement methods. The ionic charge due to the specific adsorption was obtained using the mixed-electrolyte method for both electrode charge and electrode potential as independent electrical variables. The Gibbs energy of adsorption of I- ions was calculated using the simple virial adsorption isotherm. It was found that under comparable conditions the results obtained at constant electrode potential and at constant electrode charge are coincident and the adsorption of I- anion increases in the sequence of Bi single crystal planes (111)< (001)< (01 (1) over bar) and solvents methanol < ethanol, The electrosorption valency and the effective dipole moment of the dipole formed by an adsorbed halide ion and its image charge in the Bi plane have been calculated. It was found that on the Bi(111) plane, where the chemical bonds are all saturated, the electrosorption valency has a constant value in the potential range studied while on the more active Bi planes it depends on the electrode potential. It was concluded that the effective surface dipole formed is screened by the solvent molecules and the metal electron gas significantly. The surface dipole value diminishes on moving from Bi(111) plane to more active planes.