Purpose. Reduced hospital stay and intensive care unit stay after endovascular aneurysm repair (EVAR) compared to open repair (OR) of abdominal aortic aneurysms (AAA), is expected to result in an overall reduction in costs of AAA repair. Based on a randomised trial recently concluded the cost and cost effectiveness of OR and EVAR in the first postoperative year are compared. Methods. In a multicenter randomised trial comparing OR and EVAR we randomly assigned 149 patients to OR and 151 to EVAR. Costs, cost-effectiveness and complications were determined one year after surgery. The uncertainty surrounding the cost-effectiveness ratio (iCER) in terms of costs per quality-adjusted life year (QALY) gained was addressed by bootstrapping. Results. Ten patients had died in the OR group and 9 in the EVAR group (chi-square p=0.8). In the OR group 32 patients had had one or more severe complications and in the EVAR group 27 patients (chi-square p=0.5). EVAR was associated with €4.480 additional direct costs per patient (€18.138 versus €13.659) and a slight (0.01) QALY decrease (0.73 versus 0.74, 95% CI -0.04- 0.06). In more than 60% of the bootstrap estimates OR resulted in favourable health outcomes in terms of QALYs. Also, OR appeared cost-saving with 100% certainty. In terms of complications EVAR appeared favourable with 90% certainty. From a health economic perspective, however, OR appeared preferable with 100% certainty. As longer term follow-up after EVAR may only reveal the difference in costs and effects to become more favourable for OR the current one-year time horizon suffices to make a final policy decision with regard to the currently available devices and patient selection. Conclusion. In patients suitable for both treatments, EVAR is not cost-effective.