Breaking down the redox chemistry and the electronic structure of POMs in solution into their nanophysics on surfaces, it was demonstrated that the conductivity of allvanadium Lindqvist-type POMs and the V3-substituted Well-Dawson-type POMs 10 can be manipulated by the redox states of the POMs. For instance, fully-oxidized (V V ) complexes with the POV6 core were immobilized as intact single molecules on Au(111) substrates, with no change of their valence state after the adsorption process. The electronic structure of the POV6 could, however, be modified multiple times at room temperature, when applying an external potential by the tip of a scanning tunnelling microscope (STM) acting as top electrode. The changes were detected at electrically accessible V(3d) states in a technologically relevant voltage range (< 2 V), where the injection of up to 4 electrons into the LUMOs of the POV6 core was achieved. This multi-electron modification characterized by an increasing number of V(3d) electrons is visualized by discrete conduction states with a stepwise increase of the electrical conductance caused by single electron transfer processes.