<p>In the present work, the usefulness of red mud combined with indigenous bacterial strain through the Microbially Induced Calcite Precipitation (MICP) technique for the stabilization of black cotton soil (BCS) has been demonstrated. Geotechnical properties of BCS treated with red mud and MICP are evaluated. With the addition of red mud to BCS, the maximum dry density (MDD) was found to increase from 16.03 kN/m³ to 17.52 kN/m³ while the optimum moisture content (OMC) reduced from 22.52% to 19.01%. The unconfined compressive strength (UCS) of BCS improved from 160.51 kN/m² to 735 kN/m² after treatment with red mud and further increased to 970.66 kN/m² with the combined MICP treatment. Similarly, the split tensile strength (STS) increased from 55.11 kN/m² to 339 kN/m² after MICP treatment. A reduction in soil alkalinity, with the pH decreasing from 10.66 (for red mud) to 8.77 when blended with BCS and further reduction to 7.66 through MICP treatment, was confirmed through chemical analysis. Moreover, the calcite content in soil increased by 88% compared to the untreated soil, enhancing the stabilization process. Microstructural analyses, including XRD, SEM, and FTIR, were also carried out on the soil samples after MICP treatment with the optimum red mud content. These analyses confirmed enhanced bonding between soil particles which is attributed to the higher calcite precipitation after treatments. These findings highlight the usefulness of integrating red mud and MICP techniques in soil stabilization, offering a cost-effective and eco-friendly solution for improving the engineering properties of black cotton soil.</p>