A new organic stilbazolium derivative, 1-Ethyl-2-(2-p-tolyl-vinyl)-pyridinium iodide (TASI), was grown from methanol:acetonitrile (1:3) mixed solvent by slow evaporation technique. Single crystal X-ray diffraction analysis revealed that TASI crystallizes in triclinic system with a centrosymmetric space group P-1. The molecular structure and the presence of expected functional groups of TASI were confirmed by H-1 NMR and FT-IR spectroscopic studies. The HOMO and LUMO energies influence the charge transfer takes place within the molecule. The grown crystal was thermally stable up to 210 degrees C as determined by TG/DTA analysis. UV-Vis-NIR spectral study showed that the grown crystal was transparent in the wavelength range of 438-1100 nm. Mechanical behaviour and surface laser damage threshold were studied to find the suitability of the grown crystal for device fabrication. Studies of its third-order nonlinear optical properties using a Z-scan technique demonstrates that TASI crystal is capable of exhibiting reverse saturable absorption and self-focusing performance with the second-order molecular hyperpolarizability (gamma) 4.983 x 10(-34) esu. The third-order nonlinear susceptibility of TASI was found to be 8.931 x 10(-6) esu, which is higher than a few other stilbazolium derivative crystals. (C) 2016 Elsevier B.V. All rights reserved.