Functional feed additives play a crucial role in enhancing aquaculture sustainability by improving growth, immunity, and environmental outcomes. These additives, including probiotics, prebiotics, phylogenics, and symbiotics, help improve gut health, enhance feed efficiency, and reduce reliance on fishmeal. They also contribute to better water quality and reduce the environmental footprint of aquaculture. However, challenges such as the variability of their efficacy, the need for optimal dosing, and the potential for adverse effects when used in excess remain. The use of functional feed additives can reduce the need for antibiotics and chemotherapeutics, which are harmful to both aquatic animals and the environment. Despite their benefits, the adoption of these additives is still in its early stages, and further research is needed to optimize their application. Overall, functional feed additives are a promising solution for sustainable aquaculture, offering a balance between economic, environmental, and social sustainability.Functional feed additives play a crucial role in enhancing aquaculture sustainability by improving growth, immunity, and environmental outcomes. These additives, including probiotics, prebiotics, phylogenics, and symbiotics, help improve gut health, enhance feed efficiency, and reduce reliance on fishmeal. They also contribute to better water quality and reduce the environmental footprint of aquaculture. However, challenges such as the variability of their efficacy, the need for optimal dosing, and the potential for adverse effects when used in excess remain. The use of functional feed additives can reduce the need for antibiotics and chemotherapeutics, which are harmful to both aquatic animals and the environment. Despite their benefits, the adoption of these additives is still in its early stages, and further research is needed to optimize their application. Overall, functional feed additives are a promising solution for sustainable aquaculture, offering a balance between economic, environmental, and social sustainability.