This paper demonstrates the basic properties in the systems most commonly considered for costing treatments in the Danish hospitals. The differences between the traditional charge system, the DRG system and the ABC system are analysed, and difficulties encountered in comparing these systems are discussed. A sample of patients diagnosed with stable angina pectoris (SAP) at Odense University Hospital was used to compare the three systems when costing an entire treatment path, costing single hospitalisations and studying the effects of length of stay. Furthermore, it is illustrated that the main idea behind each system is reflected in how the systems over- or underestimate costs. Implications when managing the hospitals, particularly reimbursement, are discussed.