The tetranuclear [{Pt(CNC)(tht)}(3)Tl](PF6) (tht = tetrahydrothiophene; SC4H8; CNC = C,N,C-2,6-NC5H3(C6H4-2)(2); 2) cluster has been prepared by the reaction of [Pt(CNC)(tht)] (1) and TlPF6 (molar ratio 3:1) and structurally characterized. The Tl-I atom is bonded to three Pt-II centers bearing a perfect trigonal coordination. The Pt-II-Tl-I bonds are unsupported by any bridging ligand and are the shortest of this kind reported so far [2.9086(5) angstrom]. These intermetallic bonds persist in a CD2Cl2 solution, as shown by the Pt-195{H-1} NMR spectrum of 2 at 193 K, in which a Pt-Tl coupling of 8.9 kHz is observed.