Hierarchical Condition Category (HCC) coding, launched by CMS in 2004, is essential for estimating patient healthcare costs within value-based payment models. It links approximately 10,000 ICD-10 diagnosis codes to 86 HCCs, assigning a risk adjustment factor (RAF) score based on patient demographics and health complexity. Effective HCC coding not only improves claim accuracy and revenue but also enhances the overall patient care experience by considering social determinants of health.