CONTEXT: Reconnecting crop and livestock production beyond the farm gate by exchanging raw materials (e.g., feed, manure) between farms is seen as a promising solution for improving the environmental performance of farms, since it should reduce the use of imported nitrogen (N) inputs. However, such a circular economy does not necessarily lead to a positive outcome, since cooperating farms might simultaneously intensify their production, which could cancel out the benefits of reconnecting crops and livestock: this is known as a rebound effect. OBJECTIVE: The aim of our study was to identify and analyze a potential rebound effect due to reconnection of crop and livestock farms. METHODS: We collected data on 18 case-study farms in a small territory in Spain. We then calculated two indicators of the N rebound effect: one based on potential savings of inorganic N fertilizer for cooperating crop farms and another based on potential savings of N losses to the environment for cooperating livestock farms. RESULTS AND CONCLUSIONS: On cooperating crop farms, importing manure did not lead to replacement of inorganic N fertilizer and could lead more inorganic N fertilizer being used. Thus, their mean N rebound effect was 520 %, which constituted a backfire effect. This mean, however, covered large differences among farms. On cooperating dairy farms, exporting manure resulted in a mean negative rebound effect of-17 %, meaning that they achieved higher savings in the N balance than expected compared to non-cooperating dairy farms. SIGNIFICANCE: Our main contribution is to show that there may be a rebound effect when reconnecting crop and livestock production beyond the farm gate due to the intensification of farms. The indicators of the N rebound effect developed can thus help identify situations that improve or degrade environmental performance. They should be used to complement existing indicators, such as N-use efficiency and the N balance, to design efficient farming systems while avoiding a rebound effect.