Reactions of the BH4− anion with equimolar amounts of HN(NO2)2 or of BH3⋅THF with K[N(NO2)2]− produced a mono‐substituted [BH3N(NO2)2]− anion, which contains a B−N connected dinitramido ligand. The reaction of BH4− with two equivalents of HN(NO2)2 afforded the di‐substituted borate anion consisting of two isomers, one with both nitramido ligands attached to B through N and the other one with one ligand attached through N and the other one through O. The disubstituted dinitramidoborates are marginally stable under ambient conditions, and the isomer with two N‐connected ligands was characterized by its crystal structure. A tri‐substituted borate was tentatively identified by NMR in the reaction of BH4− with a large excess of HN(NO2)2. All of the anions are highly energetic. Theoretical calculations show that the energy differences between the B−N and B−O tautomers are small, explaining the formation of both.