It was shown that physicians working at the Swedish emergency department (ED) are unaware of the costs for investigations performed. This study evaluated the possible impact of price lists on the overall laboratory and radiology costs at the ED of a Swedish university hospital. Price lists including the most common laboratory analyses and radiological investigations at the ED were created. The lists were distributed to all internal medicine physicians by e-mail and exposed above their working stations continually. No lists were provided for the orthopaedic control group. The average costs for laboratory and radiological investigations during the months of June and July 2007 and 2008 were calculated. Neither clinical nor admission procedures were changed. The physicians were blinded towards the study. Statistical analysis was performed using the Student's t-test. A total of 1442 orthopaedic and 1585 medical patients were attended to in 2007. In 2008, 1467 orthopaedic and 1637 medical patients required emergency service. The average costs per patient were 980.27 SKR (98€)/999.41 SKR (100€, +1.95%) for orthopaedic and 1081.36 SKR (108€)/877.3 SKR (88€, -18.8%) for medical patients. Laboratory costs decreased by 9% in orthopaedic and 21.4% in medical patients. Radiology costs changed +5.4% in orthopaedic and -20.59% in medical patients. The distribution and promotion of price lists as a tool at the ED to heighten cost awareness resulted in a major decrease in the investigation costs. A significant decrease in radiological costs could be observed. It can be concluded that price lists are an effective tool to cut costs in public healthcare.