<p>Heavy metal (HM) pollution poses serious risks to ecosystems and human health because of its toxicity, persistence, and ability to accumulate in living organisms. Conventional remediation methods, including chemical precipitation and adsorption, are often effective but remain costly and can produce secondary waste. Microbial bioremediation provides a more sustainable alternative by using microorganisms to transform or immobilize toxic metals. In this review, we critically evaluate the main microbial mechanisms (biosorption, bioaccumulation, and biotransformation) focusing on their efficiency, limitations, and the challenges of applying laboratory findings in real environments. Case studies and applications in wastewater treatment, groundwater remediation, mining, agriculture, and the textile industry are examined to illustrate both their potential and constraints. A comparative discussion of microbial species highlights their advantages and weaknesses under different conditions. Particular attention is given to lactic acid bacteria (LAB), which combine bioremediation capacity with probiotic and food-related benefits. Finally, we consider recent advances in genetic engineering, microbial consortia, computational modeling, and nanotechnology, which together point toward promising strategies for enhancing the scalability and effectiveness of microbial HM remediation.</p> Graphical Abstract <p></p>