The herbicide triflusulfuron-methyl (systematic name: methyl 2-{[4-dimethyl-amino-6-(2,2,2-trifluoro-eth-oxy)-1,3,5-triazin-2-yl]carbamoylsulfamo-yl}-3-methyl-benzoate) and its degradation product triazine amine [systematic name: 2-amino-4-dimethyl-amino-6-(2,2,2-trifluoro-eth-oxy)-1,3,5-triazine] form a triclinic 1:1 co-crystal of the title compound, C(7)H(10)F(3)N(5)O·C(17)H(19)F(3)N(6)O(6)S, in which its two components are connected via a pair of complementary N-H⋯N hydrogen bonds, similar to the monoclinic crystal structure of the parent compound triflusulfuron-methyl [Mereiter (2011 ▶). Acta Cryst. E67, o1778-o1779] in which a pair of mol-ecules related by a twofold axis are linked by two N-H⋯N bonds. The triflusulfuron-methyl mol-ecules of both crystal structures are similar in geometric parameters and conformation, which is due to stiffening by a short intra-molecular N-H⋯N bond [N⋯N = 2.620 (4) Å] and an intra-molecular dipole-dipole inter-action between the sulfamide and the carboxyl moieties, with O(s)⋯C(c) = 2.802 (5) Å and O(c)⋯N(s) = 2.846 (4) Å. Inter-molecular N-H⋯O hydrogen bonds and slipped π-π stacking inter-actions between the diamino-triazine moieties [perpendicular distances of 3.25 Å within hydrogen-bonded tetra-mers and 3.27 Å between adjacent tetra-mers] link the two constituents of the co-crystal into columns parallel to the a axis. An intra-molecular C-H⋯O hydrogen bond occurs in the triflusulfuron-methyl mol-ecule and inter-molecular C-H⋯O inter-actions between triflusulfuron-methyl mol-ecules occur in the crystal structure. In the triflusulfuron-methyl molecule the dihedral angle between the least-squares planes of the two rings is 75.8 (1)°. In the triazine molecule, the CF(3) group is partly orientationally disordered.