In the crystal structure of the title compound {systematic name: bis[6-methyl-1,2,3-oxathiazin-4(3H)-one 2,2-dioxide(1-)-kappa2N3,O4]bis(3-methylpyridine)copper(II)}, [Cu(C4H4NO4S)2(C6H7N)2], the CuII centre resides on a centre of symmetry and has an octahedral geometry that is distorted both by the presence of four-membered chelate rings and because of the Jahn-Teller effect. The equatorial plane is formed by the N atoms of two methylpyridine ligands and by the more basic O atoms of the acesulfamate ligands, while the weakly basic N atoms of these ligands are in elongated axial positions with a misdirected valence. The crystal is stabilized by two intermolecular C-H...O interactions involving the methyl and CH groups, and the sulfonyl O atoms of the acesulfamate group.