<p>This study focuses on the preparation of BaFe_0.5Nb_0.5O₃ perovskite doped at the A-site with 12% Mg and its structural, morphological, compositional, dielectric, electrical, and magnetic properties. The material exhibits a cubic crystal structure with Pm-3m symmetry, and its polycrystallinity is evident from surface imaging, which reveals a heterogeneous distribution of grains. Elemental analysis indicates the existence of all expected elements, with Fe and Nb having dual oxidation states. These dual oxidation states enable the hopping conduction mechanism and magnetic exchange interactions within the material. The obtained pattern from the examination of the dielectric parameters of the material is consistent with Koop’s theory and Maxwell–Wagner’s model. Analysis of impedance parameters establishes that the material exhibits the negative temperature coefficient of resistance feature and undergoes a relaxation that deviates from the ideal Debye nature. At ambient temperature, the material shows weak ferromagnetism. In summary, these findings suggest that the material could be used in the development of NTC thermistors, sensors, capacitors, multilayered capacitors, memory storage devices, etc.</p>