Background: Appropriate selection of tongue cancer patients considering surgery is critical in ensuring optimal outcomes. The American College of Surgeons' National Surgical Quality Improvement Program ('ACS-NSQIP') risk calculator was developed to assess patients' 30-day post-operative risk, providing surgeons with information to guide decision making. Method: A retrospective review of 30-day actual mortality and morbidity of tongue cancer patients was undertaken to investigate the validity of this tool for South Australian patients treated from 2005 to 2015. Results: One hundred and twenty patients had undergone glossectomy. Predicted length of stay using the risk calculator was significantly different from actual length of stay. Predicted mortality and other complications were found to be similar to actual outcomes. Conclusion: The American College of Surgeons' National Surgical Quality Improvement Program risk calculator was found to be effective in predicting post-operative complication rates in South Australian tongue cancer patients. However, significant discrepancies in predicted and actual length of stay may limit its use in this population.