The previously unknown hexakis(fluorosulfato)antimonate(V) anion has been obtained as the cesium salt by oxidation of antimony with bis(fluorosulfuryl) peroxide, S2O6F2, in fluorosulfuric acid in the presence of CsSO3F. The highly symmetric anion has crystallogarphic (exact) S-6 symmetry and features unusually short S-O (1.397(2) Angstrom) and S-F (1.486(3) Angstrom), bonds which suggests its use as a very weakly coordinating anion in superacid solution or in the solid state.