The aim was to assess costs and cost-effectiveness of additional acupuncture treatment in patients with headache compared with patients receiving routine care alone. A randomized, controlled trial was conducted, including patients (> or =18 years old) with primary headache (more than 12 months, at least two headaches/month). Outcome parameters were quality of life (Short Form 36), direct and indirect costs differences during the 3-month study period and the incremental cost-effectiveness ratio (ICER) of acupuncture treatment. A total of 3182 patients (1613 acupuncture; 1569 controls) with headache were included (77.4% women, mean age and standard deviation 42.6 +/- 12.3; 22.6% men, 47.2 +/- 13.4). Over 3 months costs were higher in the acupuncture group compared with the control [euro857.47; 95% confidence interval 790.86, 924.07, vs. euro527.34 (459.81, 594.88), P < 0.001, mean difference: euro330.12 (235.27, 424.98)]. This cost increase was primarily due to costs of acupuncture [euro365.64 (362.19, 369.10)]. The ICER was euro11 657 per QALY gained. According to international cost-effectiveness threshold values, acupuncture is a cost-effective treatment in patients with primary headache.