In the title polymeric coordination compound, [Sn(CH(3))(2)(C(2)H(2)ClO(2))Cl](n), the Sn atom has a distorted trigonal-bipyramidal geometry, with two O atoms of the ligands in axial positions and two methyl groups and one Cl atom in equatorial positions. Adjacent Sn atoms are bridged by the two O atoms of the carboxylate ligand, forming a chain structure along the a-axis direction.