The evolving paradigm of sustainable development necessitates a shift towards circular economy models that minimize waste and optimize resource use throughout the entire supply chain. Smart supply chains, driven by Artificial Intelligence (AI) and the Internet of Things (IoT), are poised to revolutionize commerce by facilitating real-time decision-making, transparency, and efficient resource management. This paper explores the integration of AI and IoT in creating smarter, greener supply chains that contribute to sustainability goals. AI enhances supply chain forecasting, predictive analytics, and automation, while IoT facilitates real-time monitoring and data-driven insights, enabling circular economy practices such as product life cycle management, reuse, and recycling. The synergy between AI and IoT supports waste reduction, energy efficiency, and sustainable sourcing practices, thereby driving businesses toward a more sustainable future. This paper discusses the key technologies, challenges, and opportunities in implementing smart supply chains for greener commerce, alongside case studies that showcase the effectiveness of AI and IoT in achieving sustainability objectives. It concludes by emphasizing the role of these technologies in fostering a circular economy and proposes future research directions for enhancing their integration in global supply chains.