A methylpyridinium tail-end polyamphiphile with a 12-methylene spacer was complexed with n-alkyl sulfonate surfactants of 4, 8, and 16 carbon lengths. The thermal and structural properties of these poly(12-methacryloyloxydodecyl-4-methylpyridinium sulfonate)s in the solid state were studied. The complexes with the two shorter surfactants self-assemble into a disordered lamellar-like morphology, with relatively short correlation lengths, similar to the parent Br-neutralized homopolymer. Two glass transition-like events are observed in the DSC thermograms and are ascribed to nanophase-separated nonionic and ionic subplanes, respectively. The complex with the longest surfactant displays thermotropic liquid crystalline behavior, with transitions between two different partially crystalline phases (related to surfactant tail-end crystallization), a smectic A-like mesophase, and the isotropic phase. Surprisingly, the lamellar spacings for all of the complexes are very similar to that of the parent polymer. Two possible structural models taking this into account are discussed.