The unusual combination of dielectric and magnetic characteristics at the nanoscale has made nanoferrites a potential material for enhanced wireless communication and sensing applications. In patch antenna design, they are perfect candidates for use as magneto-dielectric substrates because of their high resistivity, moderate magnetism, and adjustable permeability–permittivity balance. With a focus on their potential for creating small, effective, and frequency-agile antenna systems, this chapter examines the synthesis, structural properties, and electromagnetic behavior of nanoferrites. The impact of crystallographic phase, grain size, and cation distribution on dielectric constant, magnetic loss, and overall antenna performance is discussed. Antenna downsizing and bandwidth increase are investigated using mechanisms including magnetic domain dynamics, interfacial polarization, and spin resonance. Material tunability and design flexibility have been further enhanced by recent technical developments, such as additive manufacturing, polymer–ferrite composites, and thin-film ferrite deposition. Due to their improved anisotropy and frequency stability, emerging ferrite systems such as hexaferrites, garnet ferrites, and multiferroic nanocomposites are appealing for high-frequency and reconfigurable antenna platforms. The ongoing combination of nanoferrites with contemporary computational design tools and environmentally friendly processing methods offers a clear route toward next-generation, small, and highly effective patch antennas, despite lingering issues like magnetic losses and manufacturing complexity.