In the title compound, C13H9ClINO3S, the benzene rings are inclined to one another by
81.6 (2)°. In the crystal, molecules are linked by pairs of N—H⋯ O hydrogen bonds, forming
inversion dimers with an R22 (8) ring motif. The dimers are linked by C—H⋯ O hydrogen
bonds, forming sheets parallel to the bc plane. Neighbouring sheets are linked via offset π–
π interactions involving inversion-related iodobenzene rings [intercentroid distance= 3.807
(3) Å], forming a three-dimensional supramolecular structure.