The conductivity of tetra-alkylammonium halide hydrates has been studied by impedance spectroscopy in the temperature range 213-322 K. Conductivity drops around their melting point and in some cases again about 20 K below it. At 250 K it is in the range 10(-6)-10(-9) Sm-1 Linear, Arrhenius type conductivity dependence is observed for lower temperatures and corresponding activation energies of conductivity are within 0.45-0.62 eV. At a given temperature the conductivity of retra-alkylammonium halide hydrates is a few orders of magnitude lower than that of tetramethylammonium hydroxide hydrates. The reasons for this difference are discussed.