OBJECTIVES: Several observational studies have examined the epidemiological and social characteristics of patients undergoing hernia surgery, but conclusions drawn from these studies are generally limited due to the small sample population. Here we describe patient demographics of hernia repair patients and surgical expenditure using a population-based approach with a retrospective nationwide database. METHODS: Premier Inc has established one of the largest hospital databases worldwide. It collects patient data from around 500 hospitals in the US. Hernia surgery was stratified by inpatient or outpatient treatment, hernia repair surgery type (inguinal, incisional or umbilical), surgical procedure (laparoscopic or open), and the type of mesh used (flat, tissue-separating or device). Patient demographics were recorded and are presented for every cohort of patients. Surgical costs across hernia repair and mesh type cohorts are also presented.   RESULTS: Across treatment groups the majority of patients were white (~70%) with a mean age of 54 years. Inguinal and umbilical hernia repair groups were both predominantly male with low to moderate incidences of obesity and diabetes. Incisional hernia repair patients had the highest incidence of obesity (19.0%) and diabetes (18.5%) and could be equally either male (42.0%) or female (58.0%). Tissue-separating mesh (TSM) was used mainly in incisional hernia repairs, whilst other meshes were used in all surgical cohorts. TSM was used more frequently in females (60.1%) and in patients with a high incidence of obesity (22.7%) and diabetes (22.1%). No striking differences in surgical costs across the hernia repair or mesh type cohorts were observed, with average surgical costs between $2199 and $4099. CONCLUSIONS: This is the first example of extracting hernia repair patient demographics from a nationwide database. Although there are limitations to the interpretation of this data, these results are encouraging. Further development of the management, analysis and interpretation of such data is ongoing.