The title compound, [Fe(C(9)H(10)BN(6))(2)](3)[Fe(NCS)(6)] or [Fe(III)(Tp)(2)](3)[Fe(III)(NCS)(6)] [Tp is hydrotris(1-pyrazolyl)borate], crystallizes in space group R-3; the asymmetric unit comprises one-half of an [Fe(Tp)(2)](+) cation, with its Fe atom on a crystallographic inversion centre, and one-sixth of an [Fe(NCS)(6)](3-) anion, on a site of -3 symmetry. The anions and cations are stacked into a three-dimensional supramolecular aggregate via two distinct types of weak C-H.pi interactions.