The title compound, C(14)H(16)O(4)P(2)·2H(2)O, possesses a crystallographic inversion center where two -P(=O)(OH)(C(6)H(5)) groups are joined together via two -CH(2) groups. In the crystal, the acid molecules are linked by the water molecules via O-H⋯O hydrogen bonds, leading to the formation of a two-dimensional network lying parallel to (101).
