The title compound, C15H16N2O5S, is a product of the reaction of 2-(2,4-dimethoxyphenylamino)-1,3-thiazol-4(5H)-one with acetic anhydride. The presence of the acetyl and acetoxy groups in the molecule indicates that the starting thiazole exists as a tautomer in the reaction mixture with exocyclic amino and enol moieties. The acetyl group is tilted slightly from the heterocyclic ring plane [dihedral angle = 4.46 (11)°], while the acetoxy group is almost perpendicular to this ring [dihedral angle = 88.14 (12)°]. An intramolecular acetyl–methoxy C—H...O interaction is noted. In the crystal, molecules are connected into a three-dimensional architecture by C—H...O interactions.