Phytic acid (PA) is one of the widely used flame retardants (FRs) to treat a variety of fabrics owing to its high phosphorus content of ca. 28 wt% (with respect to its molecular weight), abundance, non-toxicity, and biocompatibility. The current review discusses the state-of-the-art of PA-based FRs for natural fabrics such as cotton and wool. The possibilities of making PA and FR-based multi-functional cotton fabrics having antimicrobial, conductive, hydrophobic properties are reported by virtue of the synergistic benefits associated with chitosan, silicon, nitrogen, and boron-based molecules. The factors influencing the FR behaviour as well as the durability of PA-based cotton and wool fabrics are discussed with respect to the concentration of PA, pH of the coating solution, temperature, and preparation methods. Holistically, PA has been proved to be a potential alternative to halogenated FRs to confer fire retardant property to cotton and wool fabrics.