The P atom in the title compound, C(16)H(17)Cl(3)N(3)O(2)P, is bonded in a distorted tetra-hedral geometry with the phosphoryl and carbonyl groups anti with respect to one another. In the crystal, mol-ecules are linked through (N-H)(2)⋯O(=P) and N-H⋯O(=C) hydrogen bonds into chains along [001]. The phosphoryl O atom acts as a double hydrogen-bond acceptor.