Background Older patients undergoing emergency surgery experience higher mortality and morbidity. ‘Care of Older People in Surgery’ (COPS) is a comprehensive geriatric care model developed for acute surgical units (ASU) to improve clinical outcomes in older general surgical patients. This study aimed to evaluate the impact of COPS on clinical and health service outcomes in an Australian hospital. Methods The before‐and‐after study was conducted in the ASU, at Nepean Hospital. Data from patients ≥75 years admitted for >24 h into the ASU during the intervention period between April 2017 and March 2018 were compared to patients admitted in the previous year (April 2016 to March 2017) prior to the COPS intervention (n = 212). Health service outcomes measured include the average stay length, medical emergency team response, unplanned intensive care unit admission and 28‐day readmission rates. Results The COPS group (n = 214) suffered significantly fewer medical complications, including less acute kidney injuries, arrhythmias and urinary tract infections compared to the pre‐intervention cohort (n = 212). Medical emergency team activation was significantly reduced after COPS model implementation and the average length of stay decreased. However, the incidence of postoperative delirium and acute coronary syndrome were higher in COPS cohort. Conclusion Our study demonstrated that comprehensive geriatric assessment and care delivered through a shared model of care in older general surgical patients improved clinical outcome and patient safety measures.