An inductive conductivity sensor and a method for measuring specific electrical conductivity of a medium, comprising a transmitting coil fed by means of an input signal; coupled with the transmitting coil via the medium; a receiving coil, which delivers an output signal, which is a measure for the conductivity of the medium; and surrounding the transmitting coil and the receiving coil a housing, which has, intended for immersion in the medium, at least one housing section, whose housing wall surrounds the transmitting coil and the receiving coil. The housing section includes at least a first electrically conductive contact intended for contact with the medium and a second electrically conductive contact intended for contact with the medium. The conductivity sensor includes an electrically conductive conductor and the first contact is connected with the second contact via the conductor, wherein the conductor and the electrically conductive contacts are so embodied that they form via an ionic conduction path of the medium a closed electrical current path around the transmitting coil and the receiving coil.