Carbonization (Argon atmosphere, 900 °C, 2 h) of heteroatom-enriched pyridine-bridged inorganic-organic hybrid material (HPHM) resulted in the formation of a high specific surface area (SABET of 1080 m2 g-1) carbonaceous material designated as HPHMC900. The HPHMC900 serves as an effective electrocatalyst for the reduction of nitrate in an aqueous environment to ammonia (NO3RR). Importantly, HPHMC900 demonstrated fast kinetics for the NO3RR with a low Tafel slope of 70 mV decade-1. An NH3 production yield of 21 μg h-1 mgcat-1 was obtained with a Faradaic efficiency (FE) of 88.3% at -0.4 V in a 0.1 M KNO3 electrolytic solution. The high double layer capacitance (Cdl) of 14.1 mF cm-2 corroborates high SABET and exposed active sites of HPHMC900. The maximum FEs were estimated to be 48%, 93%, and 98%, corresponding to 0.05, 0.5, and 1.0 M KNO3 with maximum NH3 production yields of 18.7, 22.1, and 39.0 μg h-1 mgcat-1, respectively. The potential of employing HPHMC900 for the NO3RR as an electrocatalyst is evident by its robust stability, high SABET, and enrichment with heteroatoms N (7.7%) and P (0.28%). Thus, this sustainable environmentally benign strategy can be used for the treatment of pollutant NO3- to produce NH3.