In the title mol-ecule, C(14)H(12)N(2)O(3)S(2), the benzisothia-zolone ring system is essentially planar and forms a dihedral angle of 67.37 (6)° with the plane of the benzene ring. In the crystal structure, mol-ecules are linked via inter-molecular N-H⋯O and C-H⋯O hydrogen bonds to form chains parallel to the b axis.