The synthesis and characterization of a C2 (ethane) linked bis(trimethylammonium) pentaborate salt, [Me3NCH2CH2NMe3][B5O6(OH)4]2 (1), is reported . Compound 1 has been characterized by 1H, 11B, and 13C NMR Spectroscopy, IR spectroscopy, thermal (TGA/DSC) analysis, and single-crystal X-ray diffraction. There are two independent crystallographic pentaborate(1-) anions in the solid-state structure and these link by H-bonds at -sites into a centrosymmetric tetrameric chain. These chains are crossed-linked by R22(8) H-bond motifs to -sites of neighbouring pentaborate tetrameric units. The [Me3NCH2CH2NMe3]2+ cations are located between these tetrameric pentaborate(1-) units.