The escalating global solid waste generation, presently surpassing 2.01 billion tons every year, underscores the critical need for improvements in landfill liner technologies to ensure sustainable waste management practices. This review paper delves into the most recent developments in landfill liner materials and plans, pointing to highlight their effect on enhancing the environmental sustainability of landfills. Conventional liners, basically comprising of compacted clay and geomembranes, have been foundational in minimizing leachate movement and gas emissions. However, the advent of new materials such as geosynthetic clay liners (GCLs), nano-composite geomembranes, and the incorporation of bio-based polymers presents a paradigm shift towards more effective and eco-friendly solutions. Composite liners like, GCLs infused with bentonite have demonstrated a remarkable decrease in hydraulic conductivity, reaching to levels as low as 1 × 10–11 m/s, in this way considerably diminishing the chance of leachate percolation. Additionally, the introduction of nano-enhanced geomembranes has driven to a 40–60% increment in puncture resistance and a notable improvement in chemical compatibility, making them more durable against aggressive leachate compositions. Integration of sustainable design principles into landfill liner systems is examined, emphasizing the importance of adaptability and resource recovery, providing valuable insights for practitioners, researchers, and policymakers committed to advancing sustainable landfill management.