Small and Medium Enterprises (SMEs) represent over 90% of global businesses and play a pivotal role in the transition to a low-carbon economy. Yet, they remain largely excluded from mainstream carbon accounting and ESG compliance frameworks due to high implementation costs, limited technical expertise, and fragmented data infrastructure. This paper presents a practical and accessible carbon accounting framework specifically designed to enable SMEs to measure, report, and manage greenhouse gas (GHG) emissions efficiently while aligning with international sustainability disclosure standards. The study begins by outlining the key structural barriers facing SMEs lack of standardized emission factors, insufficient digital infrastructure, and the disproportionate cost burden of third-party verification. It then proposes a tiered carbon accounting model that integrates simplified emission tracking tools, cloud-based data management, and modular reporting templates compatible with the GHG Protocol and ISO 14064. Leveraging scalable digital platforms, the framework employs automated data capture from utility records, transportation logs, and procurement databases, supported by machine-learning algorithms to enhance accuracy and reduce manual input. By adopting a proportional assurance approach and shared verification networks, the framework minimizes audit costs while maintaining data credibility. Case-based validation shows that SMEs can achieve up to a 40% reduction in reporting costs and a 25% improvement in emissions data accuracy using adaptive, low-code accounting systems. The paper concludes that empowering SMEs through accessible carbon accounting tools not only broadens participation in ESG reporting but also strengthens supply chain transparency, investor confidence, and collective progress toward national and global decarbonization goals.