The title compound, C(19)H(23)F(2)N(4)O(3) (+)·0.5SO(4) (2-)·2.5H(2)O, an anti-bacterial fluoro-quinolone, crystallized as a racemic twin (major twin component = 0.633) in the chiral space group P1. The asymmetric unit contains two sparfloxacinium cations, one sulfate anion and five mol-ecules of water of solvation. The bond lengths and angles of both cations are almost identical. The quinoline ring systems in the cations are essentially planar, the mean deviations from the best plane being 0.045 (2) and 0.054 (2) Å and make π-π inter-actions with each other [centroid-centroid distances of 3.692 (4) Å and 3.744 (4) Å]. The crystal structure features inter-molecular O-H⋯O, O-H⋯S, N(+)-H⋯O, N(+)-H⋯S and N-H⋯O hydrogen bonds together with intra-molecular O-H⋯O and N-H⋯O hydrogen bonds. As a result, a three-dimensional supra-molecular structure is observed.