In the title compound, C(12)H(13)NO(4)S, a systemic fungicide, the heterocycle adopts a lounge chair conformation and the dihedral angle between the ring planes is 25.8 (2)°. Inter-molecular C-H⋯O hydrogen bonds are noted in the crystal structure. Also observed is a short inter-action of a methyl-ene hydrogen atom with the π-electron system of a phenyl ring in an adjacent mol-ecule.