The title salt, C(8)H(11)N(2)O(+)·HSO(4) (-), has been synthesized by the reaction between 4-meth-oxy-benzamidine and sulfuric acid. The asymmetric unit comprises a nonplanar 4-meth-oxy-benzamidinium cation and one hydrogen sulfate anion. In the cation, the amidinium group has two identical C-N bonds [1.306 (2) and 1.308 (2) Å], and its plane forms a dihedral angle of 6.49 (8)° with the mean plane of the benzene ring. The ionic components are associated in the crystal via N-H(+)⋯O(-), resulting in chains running approximately along the b-axis direction whicg are interconnected by O-H⋯O(-) hydrogen bonds.