Gallstone ileus is a rare but significant cause of intestinal obstruction particularly among the elderly population. Symptoms are often vague and therefore a high suspicious index is required for successful diagnosis. In this report, we present the case of an 87-year-old gentleman with a background history of cholelithiasis and ileostomy for ulcerative colitis who was admitted with a 24-h history of his stoma not functioning. He had an abdominal x-ray and CT which were consistent with small bowel obstruction with no identifiable cause. He underwent an examination of his stoma under general anaesthesia which revealed a 2.5 cm gallstone wedged several centimetres near the entry point of the stoma. The purpose of this report is to highlight the importance of considering gallstones as a potential cause of a non-functioning stoma in any patient with a significant history of cholelithiasis.