OBJECTIVES: To evaluate the cost-effectiveness of fentanyl ITS (iontophoretic transdermal system - IONSYSTM) versus epidural analgesia (EA) or intravenous patient-controlled analgesia (IV-PCA) for acute post-operative pain management (POPM) from a Finnish hospital perspective. METHODS: The cost-effectiveness of IONSYSTM was assessed using a decision analytic model estimating costs (2008€) and POPM patient outcomes (pain relief, minor and major POPM-related complications) from surgery to discharge. Groups receiving 1, 2 or 3 day(s) of IV-PCA or EA were compared to groups receiving respectively 1, 2 or 3 day(s) of IONSYSTM. Pain relief data were derived from clinical trials and published literature. Complication rates were predicted from a longitudinal hospital database. Resource use included drugs, consumables, equipment, POPM-related complications and staff time, the latter derived from expert panels and a literature review. Costs were based on official tariffs and price lists. RESULTS: The costs of IONSYSTM for 1, 2 or 3-day groups were €1,825, €2,240 and €2,655. For 1 day of IV-PCA and 1, 2, 3 day(s) of EA respectively, savings were €70, and €164, €167, €174. For 2 or 3 days of IV-PCA respectively additional costs were €19 and €105. The percentage of complication-free patients was consistently higher with IONSYSTM as regards minor and major complications with increment ranges of [1.44%, 3.95%] and [0.04%, 2.29%], respectively. The percentage of patients reporting no or mild pain with IONSYSTM was the same as with IV-PCA and lower than with epidural with respective increments for 1, 2 and 3-day groups of -4.02%, -4.33% and -5.26%. CONCLUSIONS: Compared to EA, IONSYSTM offers lower costs and fewer complications. EA however offers improved pain relief. Compared to IV-PCA, IONSYSTM dominates the 1-day group and for the 2 and 3-day groups offers fewer complications at a higher cost.