The crystal structures of the tri- and tetrahydrate of tin tetrachloride, viz. diaquatetrachlorotin(IV) monohydrate, [SnCl(4)(H(2)O)(2)].H(2)O, and diaquatetrachlorotin(IV) dihydrate, [SnCl(4)(H(2)O)(2)].2H(2)O, are reported and shown to contain the cis-[SnCl(4)(H(2)O)(2)] species and water molecules in both cases. The trihydrate contains chains of the tin species linked by a single hydrogen-bonded water molecule, whilst the tetrahydrate has a three-dimensional network. In addition, there are O-H.Cl interactions present.