(PPN)[P(N-3)(6)] (2) was synthesized by the metathesis of Na[P(N-3)(6)] (1) and (PPN)N-3 (PPN+ = {(Ph3P)(2)N}(+)), allowing for the isolation and full characterization of a stable hexaazidophosphate(V) salt by P-31 and N-14 NMR, UV absorption, IR and Raman spectroscopy, elemental and thermal analyses, X-ray diffraction, and Hartree-Fock and density functional theory calculations. The colorless single crystals of 2 are triclinic, space group P1, a = 9.6296(9), b = 9.8158(9), c = 10.1414(10) angstrom, alpha = 92.635(5)degrees, beta = 93.437(5)degrees, gamma = 92.105(4)degrees, and Z = 1. The [P(N-3)(6)](-) ion of 2 is isolated in the solid state and adopts S-6 symmetry both in the crystal and in solution. Thermogravimetric analysis and differential scanning calorimetry measurements reveal a surprising thermal stability of 2 (T-dec ca. 200 degrees C). No friction sensitivity was encountered.