The order in the bilayers of a metastable gel state of the long-chain surfactant sodium sulfopropyl octadecyl maleate (SSPOM) is investigated by wide-angle X-ray scattering (WAXS) and molecular modeling. The WAXS patterns indicate an ordered and rather dense in-plane structure, consisting of hexagonally packed, untilted, and interdigitated molecules. Three hexagonal reflections are found for a 60 wt % sample. Fourier analysis of the WAXS data reveals that the spatial correlation between the chains reaches almost 50 Angstrom. The estimated area per molecule in the bilayer is 40.0 Angstrom(2). Based on the experimental results, the in-plane packing is simulated and the hexagonal arrangement of molecules proves to be energetically possible. A model packing with the majority of the sodium counterions in the water phase near the SSPOM packing surface shows the best agreement with the experimental WAXS data.