Heavy metals are persistent environmental pollutants that exhibit limited biodegradation and tend to accumulate in soil for various reasons. Various remediation methods have been developed to address soil contamination, including physical, chemical, electrical, and biological methods. However, these techniques have limitations, including high cost, low efficiency, and potential negative environmental impacts. In lieu of this, this study proposes to quantify the effectiveness of sugarcane bagasse biochar (SBB) in mitigating the bioavailability of heavy metals in clayey soil. The soil samples were artificially contaminated with copper (Cu2+) at concentrations of 100 and 500 ppm. Different proportions of SBB (1%, 2%, 5%, and 10%) were added to the contaminated soil and the retention potential was assessed using batch adsorption tests relying on inductively coupled plasma atomic emission spectroscopy (ICP-AES). The change in pH, cation exchange capacity and electric conductivity (EC) were also observed before and after adding SBB to the soil. The addition of 10% SBB led to a reduction in Cu2+ extractability by approximately 38.35%. The spiked soil pH increased (up to 8.47, 8.52, 8.74 & 8.91 units) with SBB (1%, 2%, 5%, and 10%) addition. The adsorption mechanism involved in reducing the bioavailability of Cu2+ will be discussed. This study promotes the use of SBB as a green alternative to existing conventional site remediation techniques. The efficiency of SBB in reducing the metal bioavailability in soils may vary depending on the properties of biomass used for biochar production.