Currently, challenges in generating and storing hydrogen (H2) have become major concerns, and there has been a suggestion to utilize ammonia as H2 storage and carrier, followed by on-site H2 production via ammonia (NH3) decomposition process. This article provides an examination of introduced NH3 decomposition systems along with the outlines associated with technological hurdles reported recently. Subsequently, it delves into the latest advancements in catalysts employed for NH3 decomposition, encompassing both noble and non-noble metal catalysts, as well as their multi-metal combinations. Detailed scrutiny is given to the influence of support and promoters, along with a comparative assessment of catalytic activity. Furthermore, the article lytic reactor mechanisms, rate-determining steps, and apparent activation energy. Finally, it explores recent structured reactors used for this reaction and analyzes the potential of each reactor, which facilitates on-site H2 production efficiently.