Abstract: Three new organotin(IV) complexes with 4-methyl-5-trifluoromethyl-4H-1,2,4-triazolin-3(2H)-thione {Me3Sn[N(C4H4F3N2S)]} n (1), Ph3Sn[S(C4H4F3N2)] (2), and {n-Bu2Sn[N(C4H4F3N2S)](μ-OH)}2 (3) have been synthesized and characterized by elemental, IR, 1H, 13C, and 119Sn NMR analyses and X-ray crystallography. The central tin atoms of complexes 1–3 are all five-coordinated with distorted trigonal bipyramidal geometries. Interestingly, 1 shows an infinite helical polymeric chain structure via intermolecular Sn←S interactions, however, 2 and 3 show dimeric and Sn2O2 unit structures, respectively. [Copyright &y& Elsevier]