Sodium metabisulfite is the most widely used reductant for cobalt extraction from both primary and secondary sources; however, it generates sodium sulfate, which poses environmental challenges and increases processing costs. In this work, for the first time, the carbothermic reduction of Co3⁺ to Co2⁺ in complex ores (heterogenite, CoO·OH) from Zebesha Mine in Mwinilunga, North-Western Zambia, followed by microwave-assisted leaching (MWL) using sulfuric acid (H2SO4) benchmarked against conventional leaching (CL), is demonstrated. MWL achieved approximately 98.5 per cent cobalt extraction within 30 mins, compared to 120–180 mins for conventional leaching, under optimised conditions (P80 ≈ 100 µm, solid-to-liquid ratio of 25 wt per cent, 100 W, and 60°C). XRD analysis confirmed the presence of CoO in the reduced ores, enabling effective leaching of heterogenite without the use of external reductants such as sodium metabisulfite. Furthermore, H2SO4 consumption in MWL at 214 kg/t was 40 per cent less than CL at 358 kg/t. The combination of high extraction efficiency, reduced processing time and reagent consumption, and elimination of external reductants highlights carbothermic reduction coupled with MWL as a novel and sustainable approach for cobalt extraction from primary ores, with potential applicability to secondary sources.