In the title compound, [Co(C 4H 3N 2S)(C 6H 18N 4)](Cl)PF 6, the Co III ion is coordinated by a tripod-like tetradentate ligand and a monoanionic N, S-bidentate ligand in an approximately octahedral CoN 4OS geometry. The anionic S atom of the pyrimidine-2-thiolate (pymt) ligand is coordinated in the trans position to the primary amine N atom (Nprim) of the tris(2-aminoethyl)amine (tren) ligand. The crystal structure exhibits short intermolecular N—H⋯N hydrogen bonds (N⋯N <3.2 Å), and intermolecular N—H⋯Cl and C—H⋯F contacts, leading to the formation of an infinite two-dimensional network.