In the title compound, C(17)H(20)Cl(2)NO(4)P, the P atom is bonded in a distorted tetra-hedral environment. The dihedral angle between the two benzene rings is 80.5 (1)°. In the crystal structure, inter-molecular O-H⋯O and N-H⋯O hydrogen bonds link pairs of mol-ecules into centrosymmetric dimers. These dimers, are in turn, linked by weak inter-molecular C-H⋯O hydrogen bonds into one-dimensional chains along [010]. Additional stabilization is provided by very weak C-H⋯Cl inter-actions.