Poultry is the fastest growing livestock sector worldwide, but it remains underrepresented in studies of crop-livestock integration and circular agricultural systems. This study examined the concept of circularity applied to the poultry supply chain by analyzing nitrogen (N) flows at the national scale for France. Our results show that N-use efficiency of the poultry sector increased from 39% in 1990 to 44% in 2020. In contrast, N self-sufficiency barely changed at 10%, and imports of poultry products increased sixfold. Of the total annual input of 376 kt N, 20% becomes food, 24% is recycled, and 56% is lost to the environment. We explore two pathways to increase circularity: (i) increasing N-use efficiency at each step of the supply chain as well as the percentage of manure N transferred to crop production and by-products used from slaughterhouse and processing industries and (ii) changing feed rations by using more biowaste streams.