In the title compound, C(16)H(18)NO(+)·C(6)H(4)ClO(3)S(-)·H(2)O, the cation exists in an E configuration with respect to the ethenyl bond and is slightly twisted with a dihedral angle of 9.85 (5)° between the pyridinium and the benzene rings. The anion is inclined to the cation with the dihedral angles between the benzene ring of the anion and the pyridinium and benzene rings of the cation of 78.33 (6) and 68.73 (6)°, respectively. In the crystal, the cations and anions are arranged alternately into head-to-head ribbons along the c axis, with the cationic ribbons stacked along the b axis. The crystal is consolidated by O-H⋯O hydrogen bonds, weak C-H⋯O and C-H⋯π inter-actions. π-π inter-actions with centroid-centroid distances of 3.6111 (7) and 3.6466 (7) Å are also observed.