A series of compounds, CaBi ₄ Ti ₄ O ₁₅ (CBT), SrBi ₄ Ti ₄ O ₁₅ (SBT), and BaBi 4 Ti 4 O ₁₅ (BBT), belonging to the Aurivillus-type structure (four layers) has been prepared by a modified chemical route. Different oxalates were precipitated from their respective nitrate solution onto the surface of TiO ₂ powders. The room temperature x-ray diffraction study reveled that the compounds were having orthorhombic symmetry. Considering the tolerance factor, a significant deformation of the perovskite block is observed and that decreases with increase in ionic radius of A site atom. Temperature dependent dielectric study showed normal ferroelectric to paraelectric transition well above the room temperature except for BBT. The BBT ceramic showed a relaxorlike behavior near phase transition. The quantitative characterization and comparison of relaxor behavior were based on empirical parameters γ and ΔT _res . The dielectric relaxation rate follows the Vogel–Fulcher relation with activation energy =0.02 eV and freezing temperature =362 ° C . All these measurements confirmed its relaxorlike phase transition.