The title compound, [Cu(2)(CF(3)SO(3))(2)(C(3)H(9)PS(3))(2)](n), crystallizes as infinite chains in which two trimethyl trithio-phosphite ligands and two trifluoro-methane-sulfonate anions bridge the essentially tetra-hedrally coordinated Cu(I) ions in an alternating fashion. The P and one S atom of each trimethyl trithio-phosphite ligand are employed for coordination. The mol-ecular structure exhibits the rare motif of copper(I) bridged by two trifluoro-methane-sulfonate anions generating eight-membered rings.