As an extension of recent findings on the recovery of palladium with dithioether extractants, single crystals of the chelating vicinal thioether sulfoxide ligand rac-1-[(2-methoxyethyl)sulfanyl]-2-[(2-methoxyethyl)sulfinyl]benzene, C(12)H(18)O(3)S(2), (I), and its square-planar dichloridopalladium complex, rac-dichlorido{1-[(2-methoxyethyl)sulfanyl]-2-[(2-methoxyethyl)sulfinyl]benzene-κ(2)S,S'}palladium(II), [PdCl(2)(C(12)H(18)O(3)S(2))], (II), have been synthesized and their structures analysed. The molecular structure of (II) is the first ever characterized involving a dihalogenide-Pd(II) complex in which the palladium is bonded to both a thioether and a sulfoxide functional group. The structural and stereochemical characteristics of the ligand are compared with those of the analogous dithioether compound [Traeger et al. (2012). Eur. J. Inorg. Chem. pp. 2341-2352]. The sulfinyl O atom suppresses the electron-pushing and mesomeric effect of the S-C-C-S unit in ligand (I), resulting in bond lengths significantly different than in the dithioether reference compound. In contrast, in complex (II), those bond lengths are nearly the same as in the analogous dithioether complex. As observed previously, there is an interaction between the central Pd(II) atom and the O atom that is situated above the plane.