(E)-1-Methyl-4-styrylpyridinium iodide monohydrate

In the title compound, C(14)H(14)N(+)·I(−)·H(2)O, the cation is essentially planar, with a dihedral angle of 2.55 (7)° between the pyridinium and phenyl rings, and exists in an E configuration with respect to the ethenyl bond. In the crystal structure, the cations are stacked in an anti­parallel manner along the a axis. The cation is linked to the water mol­ecule by a weak C—H⋯O inter­action, and the water mol­ecule is further linked to the I(−) ion by O—H⋯I hydrogen bonds. The crystal structure is consolidated by these inter­actions and is further stabilized by a π–π inter­action between the pyridinium and phenyl rings with a centroid–centroid distance of 3.6850 (8) Å.