In the dinuclear title compound, [Na(2)(C(13)H(15)ClN(5)O(5)S)(2)(H(2)O)(6)](n), two Na(+) cations, disposed about a centre of inversion, are linked by two bridging water mol-ecules. The coordination geometry is based on an O(5) donor set defined by four water mol-ecules and a 4-amino-benzene-sulfonate O atom in a distorted trigonal-bipyramidal geometry. In the crystal, significant O-H⋯O, O-H⋯N and N-H⋯O hydrogen bonds lead to the formation of a three-dimensional architecture.