The autoreduction of ammonium pertechnetate in solutions of trifluoromethanesulfonic acid (triflic acid, TfOH) and trifluoromethanesulfonic anhydride (triflic anhydride, TfOTf) results, in the presence of sodium ions, in the formation of the complex Na2[(TcVO)(OTf)5] · 2(TfOH). Its structure has been determined by single-crystal X-ray diffraction.