This work presents the synthesis and structural characterization of [4-(1H-benzo[d]imidazol-2-yl) phenoxy]phthalonitrile, a phthalonitrile derivative carrying a benzimidazole moiety. The compound crystallizes as its dimethyl sulfoxide monosolvate, C21H12N4O center dot(CH3)(2)SO. The dihedral angle between the two fused rings in the heterocyclic ring system is 2.11 (1)degrees, while the phenyl ring attached to the imidazole moiety is inclined by 20.7 (1)degrees to the latter. In the crystal structure, adjacent molecules are connected by pairs of weak intermolecular C-H center dot center dot center dot N hydrogen bonds into inversion dimers. N-H center dot center dot center dot O and C-H center dot center dot center dot O hydrogen bonds with R-2(1)(7) graph-set motifs are also formed between the organic molecule and the disordered dimethyl sulfoxide solvent [occupancy ratio of 0.623 (5):0.377 (5) for the two sites of the sulfur atom]. Hirshfeld surface analysis and fingerprint plots were used to investigate the intermolecular interactions in the crystalline state.