The Ministerial Decree on Biomethane (15 September 2022), approved by the Italian government, promotes advanced biomethane production, supported by 1,73 billion euros from the PNRR. The goal is to reach 2,3 bcm/year by 2026, aligning with Italy’s PNIEC strategy. The 2023 PNIEC revision targets 5,7 bcm/year by 2030, aiding the phase-out of Russian gas, transport decarbonization, and waste valorization. The study estimates the maximum availability of biomethane feedstocks in Italy (2022), considering the lack of a national tracking system. Various data sources are used to assess theoretical biomethane potential based on biochemical methane potential coefficients, estimating a value equal to 5.654.043.573 cm/year.