Algeria, Africa's largest natural gas producer and a major European Union gas supplier, has limited basin-scale assessment of oil and gas methane emissions. Here, we use MethaneSAT observations from September 2024 to May 2025 to quantify methane emissions across three Algerian production regions representing 73% of national onshore production. Total methane emissions are 18 t h⁻¹ [11–25] in Hassi R'Mel, 25 t h⁻¹ [14–39] in Illizi-Ghadames, and 48 t h⁻¹ [31–65] in Oued Mya, with gas production-normalized intensities of 0.5%, 1.7%, and 6.9%, respectively. Energy-normalized methane intensities are 0.07, 0.19, and 0.22 kg CH₄ GJ⁻¹, respectively, with oil-dominant Oued Mya exceeding gas-dominant Hassi R'Mel by roughly threefold. Across the three basins, total methane emissions are 85 t h⁻¹ [58–113], including ~80 t h⁻¹ attributable to oil and gas, at a gas production-normalized intensity of 1.5% and energy-normalized intensity of 0.15 kg CH₄ GJ⁻¹. Our results substantially exceed the 0.2% methane intensity benchmark underpinning the Oil and Gas Decarbonization Charter's near-zero 2030 ambition, and exceed the Global Fuel Exploitation Inventory v3 bottom-up estimate of 61 t h⁻¹ by more than 25%. Continued Algerian basin-level monitoring is important for effective methane mitigation, especially as EU Methane Regulation (2024/1787) import intensity thresholds take effect by 2030.