Electrochemical C-N coupling to synthesize urea from NO3 -and CO2 is not thoroughly investigated in the literature, and in this work, we performed a thorough catalyst screening and reported that Ag is selective, active, and stable for the electrochemical synthesis of urea. CO2 transport to the Ag surface and adsorption are limiting factors as in the case of electrochemical CO2RR. It is demonstrated that GDE configuration overcomes the limitation and a very high urea current density of ~-100 mA/cm 2 and a urea Faradaic efficiency of ~100 % is observed at -1.25 V vs. RHE. which is the highest so far reported in the literature. The concentration of NO3 -plays a key role in the selectivity, and a minimum concentration of 0.1 M KNO3 is required for ~100 % selectivity, and at lower concentrations of NO3 -CO2RR becomes dominant instead of USR. Our DFT calculations reveal that on Ag (100), a combination of facile first and second C-N bond formation steps and an endergonic formamide formation step from *CONH2 results in its improved kinetics and selectivity towards urea synthesis. We believe that the current work would potentially lead to further studies on the electrochemical C-N coupling for high value-added chemicals.