<p>Perovskite-type oxides based on SrFeO₃ have attracted significant attention due to their rich defect chemistry, oxygen non-stoichiometry, and multifunctional properties relevant to energy conversion and electronic applications. This research work focused on the material properties of SrFeO₃ ceramics by systematically replacing iron with zirconium (Zr), as a series of SrFe_{(1−<i>x</i>)}Zr_<i>x</i>O₃ (<i>x</i> = 0.05–0.20), synthesized via the conventional solid-state reaction technique. The X-ray diffraction (XRD) analysis confirmed the successful integration of the ceramic samples and they all maintained the fundamental tetragonal perovskite structure, with systematic peak shifts indicating lattice distortion induced by Zr incorporation. The FTIR revealed modifications in Fe–O bonding and the possible formation of oxygen vacancies due to Zr substitution. Detailed crystallite size and strain analyses using multiple models (Debye–Scherrer, Williamson–Hall, Halder–Wagner, Modified Scherrer, and Size–Strain Plot) provided comprehensive insight into defect-induced microstructural evolution. The microstructure was evaluated using scanning electron microscopy (SEM). The observations showed a non-monotonic growth of the grain size. The UV–Vis spectroscopy analysis indicated that the optical band gap (E_g) has decreased throughout the compositions and enhancing capacity to absorb light in the visible spectrum. The dielectric constant showed a noticeable decrease as the measurement frequency increased, characteristic of typical polarization mechanisms. Moreover, the compositions exhibited different relaxation phenomena, which varied with the Zr content (<i>x</i>), which attributed to the complex interaction of lattice defects and charge carriers induced by the Zr substitution, offering valuable insights for their potential use in energy-related and functional oxide devices.</p>