The reaction of azide with organotellurium(VI) halides Ph(5)TeBr and cis-(biphen)(2)TeF(2) (biphen = 2,2'-biphenyldiyl) resulted in the formation and isolation of Ph(5)TeN(3) (1) and cis-(biphen)(2)Te(N(3))(2) (2), which are the first tellurium(VI)-azide species. In addition to spectroscopic data, both crystal structures have been determined. Furthermore, the stability of possible Te(VI) species with higher azide contents Ph(x)()Te(N(3))(6)(-)(x)() and Me(x)()Te(N(3))(6)(-)(x)() as well as the syntheses and properties of their Ph/Me(x)()TeF(y)() precursors was investigated, including the crystal structure determination of trans-Ph(2)TeF(4) (3). Ab initio and density functional studies of all molecules regarding the structures and electronic populations were performed.