In recent years, the catalysts for ammonia synthesis have been remarkably redeveloped, starting with the report of Ru supported by an electride in 2012. Several catalysts supported on not only electrides but nitrides and hydrides or without supports have also been reported one after another, which have high activity under mild reaction conditions. Homogeneous catalysts for ammonia synthesis at room temperature and atmospheric pressure have also continued to develop since 2003. These catalysts are very promising in solving the problems mentioned above. However, to the best of our knowledge, no research has investigated how economically advantageous these catalysts are in a process that correctly reflects their surprisingly high performance. There are numerous examples of evaluating the performance of ammonia synthesis loops. Still, they employ conventional iron-based catalysts or assume unrealistic catalytic activities such as reaching equilibrium immediately or that the reaction activity is constant under various conditions. Investigating the cost structure of the synthetic loops with recent catalysts is crucial. It will reveal the conditions they are advantageous, how they can be made more economically viable, and the direction for future catalyst development.