The title compound, C₂₁H₂₁NO₇S₃, consists of an SO₂ON(SO₂)₂ central fragment and three terminal 4-methylphenyl groups each attached at a sulfonyl S atom. The most obvious characteristic is the presence of two nearly face-to-face benzene rings, with their centroids separated by a rather short distance [3.7808 (18) Å], but with a rather slanted relative orientation [dihedral angle = 20.63 (13)°] so as to preclude a strong intramolecular π–π interaction. The third benzene ring is nearly perpendicular to the other two [dihedral angles = 71.62 (14) and 70.4 (13)°]. The packing of the structure is directed by two C–H⋯O hydrogen bonds involving aromatic H atoms (methyl H atoms are strictly non-interacting), which define chains running in the [100] direction. These one-dimensional chains evolve parallel to each other and exhibit no significant lateral interactions.