<p>For the next generation of energy storage systems, electrode materials have drawn a lot of interest. Acquiring high specific capacitance, strong chemical stability, extended longevity, and natural abundance are the primary goals for the researchers. Metal phosphates with open-framework structures have higher electrochemical performance in contrast to their related oxides, sulfides, and hydroxides. This paper provides an overview of the newest developments in the engineering and design of metal phosphate-based electrode materials for supercapacitors. Regarding their structure and associated electrochemical performance, the review will specifically concentrate on three different types of metal phosphates: single metal phosphates, double metal phosphates, and composites of metal phosphates with carbon-based materials. A variety of experimental synthesis methods, structures of materials, and electrochemical characteristics are examined. The review will wrap up with a viewpoint that highlights the benefits and drawbacks of phosphate-based supercapacitor electrodes as well as potential future research areas. Research on metal phosphate (MPs)–based electrode materials and their composites in supercapacitor applications is limited.</p>