3-Methyl-2-vinyl­pyridinium phosphate

In the title salt, C₈H₁₀N⁺·H₂PO₄⁻, the cation is essentially planar (r.m.s. deviation = 0.063 Å). In the crystal, the phosphate anions form inversion R₂²(8) dimers via pairs of O—H...O hydrogen bonds. These dimers are further linked by pairs of O—H...O hydrogen bonds, also enclosing R₂²(8) loops, forming chains running along [001]. The cations are bonded to the anions via N—H...O hydrogen bonds and C—H...O contacts.