CiNURGi (Circular Nutrients for a Sustainable Baltic Sea Region) is an Interreg Baltic Sea Region Core Project accelerating the circular economy for nutrients across the region. By strengthening infrastructure, technology, and policy, the project advances recovery and safe return of nutrients from agricultural, municipal, and industrial streams. CiNURGi is aligned with the HELCOM Baltic Sea Regional Nutrient Recycling Strategy, the EU Circular Economy Action Plan under the European Green Deal, and the Farm to Fork Strategy’s Integrated Nutrient Management Action Plan. The project runs from November 2023 to October 2026. This report corresponds to Work Package 1, Activity 1, which maps nutrient-rich biomasses and their current treatment in the Baltic Sea Region. It establishes a comparable baseline for the status of nutrient recycling in the region’s EU Member States, providing a clear starting point for targeted measures and enabling cross-border learning where countries are at different stages. We acknowledge the contribution of our consortium, 24 partners and 13 associated organizations, from Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, and Sweden. Their commitment and expertise are essential to the project’s progress. For more information about CiNURGi and its activities, please visit our project homepage: https://interreg-baltic.eu/project/cinurgi/ Version 1.0 — 22 September 2025