Cyclic octathiotetraphosphetanes, and speciafically their ammonium salt, represent novel polyfunctional heterocyclic ligands that are valuable in the development of organometallic and coordinated chemistry. Coordination features of octathiotetraphosphetane ammonium salts with structures differing only by piperidine and triethylamine substituents in the reaction with transition d‐metals of I and VIII groups [Cu(I), Ag(I), Fe(II), Co(II)] are described. Some similarities and differences in the behavior of piperidinium and triethylammonium salts of the octathiotetraphosphetane upon complexation with metal halides are discussed.