In aprotic solvents such as dimethylformamide, acetonitrile or dimethylsulphoxide, the mechanism of electrochemical reduction of 1,2,4,6-substituted pyridinium cations was investigated. The stability of the key intermediate in the overall two-electron reduction, ie of the neutral radical, was increased by substituting the positions 2, 4 and 6 by phenyl groups. The measurements were carried out by dc polarography and cyclic voltammetry at mercury, platinum and carbon electrodes.