The crystal structure of anhydrous bis(benzylaminium) 5-sulfonatosalicylate, 2C7H10N+·C7H4O6S2−, from the reaction of benzylamine with 5-sulfosalicylic acid, shows the presence of a dianionic 5-sulfonatosalicylate species, uncommon among proton-transfer compounds of this acid with organic Lewis bases. Hydrogen-bonding interactions between both aminium N+—H groups of the two cations and both the sulfonate and carboxylate O-atom acceptors of the anions give a layered two-dimensional network structure.