In the title salt, C(11)H(21)N(2) (+)·C(6)H(5)O(3)S(-), which has two cation-anion pairs in the asymmetric unit, the two imidazolium cations are linked to two separate acceptor O atoms of one of the benzene-sulfonate anions through aromatic C-H⋯O hydrogen bonds, while the second anion is unassociated.