This study comprehensively investigates the potential of using fly ash, bottom ash, and wood ash as soil stabilizers to enhance the engineering properties of an unstabilized soil. The researcher employed a Taguchi design to develop multivariate multiple regression models to accurately predict the liquid limit, plastic limit, and California Bearing Ratio of the soil-ash mixtures, considering the proportions of the ash components as independent variables. A comprehensive residual analysis was conducted to validate the models, confirming their reliability and ability to capture the complex relationships between ash content and soil behavior. The results indicate that the strategic incorporation of these waste materials can significantly improve the overall engineering performance of the soil. Notably, using the CBR model, the optimal ash content was identified as 18% fly ash, 12% bottom ash, and 0% wood ash, which yielded the highest CBR value, a critical parameter for pavement design and construction. This research makes a valuable contribution to the growing body of knowledge on the utilization of waste materials in soil stabilization, providing a practical framework for assessing the feasibility and performance of these materials in geotechnical applications. The findings offer valuable insights and guidance for engineers and practitioners seeking to leverage waste materials to improve the properties of unstabilized soils, particularly for road development projects that require robust and reliable soil foundations.