A fabric-softening composition comprising (a) alkoxylated thiodiglycol sulfoxide derivataives or thiodiglycol sulfone derivatives corresponding to formula I ##STR3## wherein X.sub.1 and X.sub.2 may be the same or different and represent a hydroxyl-substituted alkyl radical containing 8 to 30 carbon atoms, an acyl radical of an alkyl monocarboxylic acid containing 8 to 30 carbon atoms, and X.sub.1 or X.sub.2 may be hydrogen, R represents hydrogen or methyl, z is 1 to 2, n is 0 to 25 and m is 1 to 25 and (b) an anionic or nonionic surfactant or mixtures thereof.