Objectives. In 2006 South Australia had a red cell issue rate, measured as product issues per 1000 population, 22.4% higher than the national average. A pilot study was undertaken to investigate the disparity in issue rates between SA and the national average with a secondary aim of establishing information on SA red cell use. Methods. A linked electronic database was developed using clinical, epidemiological and red cell transfusion data within hospitals in the SA public sector. Aggregated red cell use across the SA public health sector was analysed by clinical variables such as Diagnosis Related Group (DRG), including speciality related groups (SRGs) and major diagnostic categories (MDCs). The DRGs that were associated with blood use were identified and applied to national hospital separations data in order to derive comparative blood utilisation rates for SA and Australia. Results. Although blood issue and usage by population measure showed a significant difference of 22.4 and 22.0% respectively between SA and Australia, when measured against weighted separations the differences reduced to 7.4 and 7.1% respectively. Conclusion. This study showed the importance of analysing blood issues and utilisation on an activity adjusted basis rather than a raw per capita basis. What is known about the topic? Transfusion practice can be monitored by various methods such as retrospective review of medical records and blood orders, prospective audits and analysis of blood usage by DRG classification. Blood utilisation studies have been used to describe the use of blood for a whole population or hospitals in order to understand the clinical reasons for transfusion. These studies also help to describe current practice, assess variability in practice and suggest areas where improvements in transfusion practice could be achieved. What does this paper add? This study enabled an analysis of red cell usage in South Australia and the factors that can influence blood utilisation rates. This study also emphasised the fact that blood usage is better represented on a hospital activity basis rather than by raw population. What are the implications for practitioners? The major implications for health practitioners would be the key findings related to red cell usage patterns. Firstly, older patients (65 years) represented 36.5% of admissions and received 56.9% of the total red cells transfused. This has huge implications for future red cell use as an ageing population will both drive up demand and also result in a decreasing red cell donor pool. Secondly, high use of red cells in medical diagnoses such as haematology, medical oncology and gastroenterology confirms the current trend towards increasing use of red cells in medical diagnoses. This implies the need to focus on reducing reliance on blood use for medical patients and improve transfusion practice by regular audits, dissemination of guidelines and education.