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Ammonia is emerging as a liquefied and renewable‐energy carrier of global interest in the future. The electrochemical reduction of nitrate is widely acknowledged as an alternative to the traditional Haber–Bosch process for ammonia production. However, it is observed that certain catalysts can undergo spontaneous oxidation–reduction reactions with nitrate to some extent, leading to the calculated ammonia Faradaic efficiency exceeding 100%. However, there is a lack of accurate experimental validation as well as effective solutions. To address these problems, it is verified that the spontaneous reaction between the catalyst and nitrate impacts on the calculation of electrocatalytic nitrate reduction performance. Meanwhile, an updated and optimized experimental strategy is proposed to address the interference caused by the spontaneous reaction. This work will significantly contribute to more accurate and reliable electrocatalytic nitrate reduction research. [ABSTRACT FROM AUTHOR]

• Electrocatalytic reduction of nitrogen-containing pollutants to ammonia are reviewed. • Strategy to improve NO solubility and product separation of NH 3 are proposed. • Strategies to achieve high performance of NO 3 − reduction to NH 3 are presented. • Strategies to enhance the performance of NO 2 − reduction to NH 3 are displayed. Nitrogenous pollutants have caused serious environmental pollution, which endangers human life and ecological environment. The electrochemical nitrogenous pollutants reduction to ammonia driven by clean electric energy has been considered as an ideal technology for the recovery and utilization of nitrogenous pollutants. Unfortunately, the electrochemical reduction of nitrogenous pollutants has long been limited by low solubility, slow mass transfer, low partial current density, and competitive hydrogen production. Recently, technologies such as gas diffusion electrodes, enrichment of reactant on catalysts surface and tandem catalytic sites have been applied to solve these problems and surprising progress has been made. In order to reduce the driving voltage of the actual two electrode electrolytic cell, some small molecules (hydrogen sulfide and glycerol) are used as backup oxidation reaction to replace slow kinetic oxygen evolution reaction, with nitrogenous pollutants reduction reactions as cathode reaction. In addition, efficient nitrogenous pollutants catalysts are also used to construct clean batteries for simultaneous nitrogenous pollutant recovery, ammonia synthesis, and electrical energy output. It is worth noting that nitrogenous pollutant reaction can also be combined with carbon dioxide reduction reaction to achieve the synthesis of carbon nitrogen compounds, which further expands the application scope of nitrogenous pollutant reaction. The research progress in the field of nitrogenous pollutants reduction is highlighted in this review. Finally, challenges facing and possible development direction in the future are presented. This review will hopefully provide suggestions for the industrial application of the electrochemical reduction of nitrogenous pollutants. [ABSTRACT FROM AUTHOR]