<p>Growing waste generation makes waste management crucial for sustainability. Decentralized systems offer ecological, logistical, economic, and social benefits but face challenges like higher costs and emission control issues. This study analyzes the environmental impact of decentralized food waste management in urban areas, considering territorial factors and decentralization evolution. Using Life Cycle Assessment (LCA), the study compares the environmental benefits of decentralized versus centralized systems, with a focus on anaerobic digestion and composting at local and municipal levels. LCA was applied to assess different impact categories. The food waste analyzed includes materials from households and large producers like markets, hotels, and restaurants. The results show that landfilling (scenario 1) has the highest impact in 88% of impact categories. Environmental impacts decrease as food waste treatment increases, with household waste treatment showing net negative impacts. The gradual implementation of food waste collection reduces environmental impacts, and further decentralization, through decentralized composting, contributes to these reductions. Scenarios involving anaerobic digestion demonstrate lower environmental impacts due to energy and material recovery. Overall, as food waste treatment increases and landfilling decreases, environmental impacts are significantly reduced. The study concludes that increasing food waste collection and treatment, along with decentralized management, reduces environmental impacts. Anaerobic digestion outperforms composting in reducing impacts. The optimal scenario involves 50% of food waste and treatment of the remaining 50% by anaerobic digestion, as well as treatment of 100% of food waste from large producers using the same technology. The most favourable scenario among those modelled reduced global warming potential by 128% compared to current landfilling practice.</p> Graphical Abstract <p></p>