In order to reduce the greenhouse gases emissions from French agriculture and particularly those of N2O, we studied the attenuation that could be allowed by a decrease in the use of mineral nitrogen fertilization on annual crops, in France. We estimated the total attenuation at the 2030 horizon and the cost of these actions for the farmer, expressed per ton of CO2e avoided. The technical actions studied concerned a better and larger implementation of the N balance to calculate N fertilizer rate, improving fertilizer efficiency through adapted practices (timing, N placement, nitrification inhibitors), and increasing surfaces grown with legumes in arable crop rotations and grasslands. Our calculations indicate a reduction in the range 15-30 kg N / year / ha affected by each measure. The mitigation potential would be important in 2030 (without modifying production levels) because of the large areas concerned – especially for improving and extending rational N fertilization and its management. Most of the proposed measures would have negative or slightly positive costs, because they represent a saving of inputs. Implementation still requires additional technical references and consistent changes in the French socio-technical system from all stakeholders.Read less <