In the molecule of the title compound, C 15H 15NO 4S, the dihedral angle between the two rings is 88.05 (7)°. The methyl ester group is nearly coplanar with the adjacent ring [dihedral angle = 2.81 (10)°], whereas it is oriented at 86.90 (9)° with respect to the plane of the ring attached to the –SO 2– group. Weak intramolecular C—H⋯O hydrogen bonding completes S(5) and S(6) ring motifs. The molecules form one-dimensional polymeric C(8) chains along the [010] direction due to N—H⋯O hydrogen bonding and these chains are linked by C—H⋯O hydrogen bonds, forming a three-dimensional network.