Densities and relative permittivities, at T=303.15 K, in the binary mixtures of sulfolane with ethylene glycol, diethylene glycol, triethylene glycol and tetraethylene glycol have been measured as a function of composition. From the experimental data excess molar volumes and the deviations in the relative permittivity from a mole fraction average have been calculated. The results are discussed in terms of intermolecular interactions and structure of studied binary mixtures. (c) 2007 Elsevier B.V. All rights reserved.