A bis-benzimidazolium nitrate salt was isolated and then characterized by FT-IR, NMR, LC-MS and UV-Vis. spectroscopies and elemental analysis. Geometry of the compound has been confirmed by single crystal X-ray study. The electronic structure and solution spectra have been supported by DFT and TDDFT calculations at HSEH1PBE/cc-pVDZ level of theory. The two-dimensional fingerprint plots associated with the Hirshfeld surface analysis of the compound elegantly quantify the interactions within the crystal structure, revealing significant similarities in the interactions. Structural parameters and spectroscopic properties of the compound are well represented by DFT and TD-DFT calculations.