OBJECTIVES: The department of Dermatology of the University hospital Maastricht performed a randomised trial to compare the cost-effectiveness of surgical excision (SE) and Mohs Micrographic surgery (MMS) in a group of patients with primary and recurrent facial Basal Cell Carcinoma (BCC) . METHODS: Hospital costs , recurrence rates and quality of life data (NHP and STAI) were collected during a time period of 18 months. The Incremental Cost Effectiveness Ratio's were calculated based on incremental costs per recurrence avoided, both for primary and recurrent BCC. The reliability of the ICER was estimated by means of bootstrap simulations. RESULTS: In total 408 primary BCC and 204 recurrent BCC were randomised to either SE or MMS. The ICER for primary BCC amounted to €25.200. Seventy-four percent of all ratio's were within the quadrant where MMS is more effective but also more costly. Twenty-four percent of all ratio's were in the quadrant where SE dominates. The ICER for recurrent BCC amounted to €7.733. All ratios were within the quadrant where MMS is more effective but also more costly. For both primary and recurrent BCC group, quality of life was not statistically significant different between SE and MMS. CONCLUSIONS: Based on costs and the recurrence rates, it is not cost-effective to introduce MMS for primary BCC on a large scale. However, other aspects like the patient perspective have not been examined in this study. It is possible that patients have a specific preference for either one of the two treatment modalities. For the recurrent BCC both ICER and bootstrap results should be treated with caution since only fifty percent of the patients with recurrent BCC have completed their 18-month follow-up. Possible changes in the recurrence rate may have a considerable effect on the final cost-effectiveness ratio of this group.