4-{2-[4-(Dimethyl-amino)-phen-yl]ethen-yl}-1-methyl-pyridinium 2,4,6-trimethyl-benzene-sulfonate monohydrate.

In the crystal structure of the title organic salt, C(16)H(19)N(2) (+)·C(9)H(11)O(3)S(-)·H(2)O, the cations pack head-to-tail within a sheet and are aligned in opposite directions in neighboring sheets. The benzene ring of the anion makes an angle of 76.99 (6)° with the plane of the cationic chromophore. The cations are situated in the ab plane, whereas the benzene rings of the anions lie in the ac plane.