In the title compound, C(15)H(11)NO(4)S, the benzothia-zole unit is essentially planar [maximum deviation = 0.0644 (14) Å for the N atom] and forms a dihedral angle 54.43 (6)° with the phenyl ring. In the crystal structure, weak bifurcated C-H⋯O hydrogen bonds involving the carbonyl O atoms as acceptors result in R(2) (2)(7) ring motifs.