Carrapateena, a breccia-hosted iron oxide copper-gold (IOCG) deposit in South Australia, commenced sub level cave (SLC) mining in 2019. Establishing robust reconciliation processes during the initial years of production was critical for aligning geological models, cave flow predictions, and operational performance. This case study outlines the development of a systematic end-of-month reconciliation framework integrating material tracking, sensitivity analyses, and consistent terminology across geology and mining teams. Challenges presented include discrepancies in tonnes and grade reconciliation, particularly gold overperformance linked to unmodelled structural features, and variance in tonnage attributed to stockpile density assumptions and weightometer calibration. Investigations using radio frequency identification (RFID) tracking and calibration reviews improved understanding of material flow and measurement accuracy. Results demonstrate that reconciliation at Carrapateena requires balancing precision with practicality, emphasizing trend analysis over short-term anomalies. The approach has enhanced transparency in performance metrics and informed continuous improvement in estimation and cave management practices. This case study provides insights into reconciliation complexities in SLC operations and highlights strategies for managing uncertainty in high-variability underground mining environments.