We have grown (NaCl) _x (NaBr) _y−x (NaI)_1−y crystals for various values of x and y by the melt method. Densities and refractive indices of all the grown crystals were determined and used for the estimation of composition in the crystal. Lattice parameters were determined from the X-ray powder diffraction data. DC and AC measurements were done at various temperatures ranging from 40 to 150°C. Activation energies were also estimated. The bulk composition has complicated influences on the electrical properties.