The title compound, C(7)H(8)NO(2) (+)·H(2)PO(3) (-), is formed from alternating layers of organic cations and inorganic anions stacked along the a-axis direction. They are associated via O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonding, giving rise to two different R(2) (2)(8) graph-set motifs and generating a three-dimensional network.