Purpose Pelvic exenteration (PE) is a radical procedure involving multi-visceral resection for locally advanced primary or recurrent pelvic malignancies. Such radical surgery is associated with prolonged theatre time and hospital stay, as well as a substantial risk of postoperative complications, and therefore significant financial cost. The aim of this study was to report the inpatient cost of PE at a specialist centre in the Australian public sector. Methodology A retrospective costing review of consecutive PE operations at Royal Prince Alfred Hospital in Sydney, between March 2014 and June 2022 was performed. Clinical data was extracted from the medical record and institutional databases, and in-hospital costing data was provided by the SLHD Performance Unit. All statistical analysis was completed using SPSS. Results A total of 461 patients underwent PE. 283 (61.4%) underwent PE for primary or recurrent rectal cancer, 160 (34.7) for primary or recurrent non-rectal cancer, and 18 (3.9%) for benign indications. The median admission cost was $102,910, with operating room costs, followed by medical and nursing costs most significant. The total cost was similar for rectal and non-rectal cancer (p = 0.590), however, was higher for complete compared to partial PE (p <0.001), and PE for recurrent compared to primary malignancy (p = 0.002). Conclusion The total admission cost of patients undergoing PE reflects the complexity of the surgical treatment and the multidisciplinary team required. Costs increase when PE is indicated for recurrent malignancy and when a complete, rather than partial, PE is required. Strategies to reduce the cost of PE could focus on reducing operating room costs and post-operative length of admission.