OBJECTIVES: Migraine is a common disabling primary headache disorder, with high prevalence and socio-economic and personal impacts. In the Global Burden of Disease 2015, it was ranked the third-highest cause of disability worldwide in both males and females under the age of 50 years. In Brazil, affects around 15.8% of adults, consuming more health care resources as the general population. This study analyzes economic impact of migraine in a health plan. METHODS: Observational case-control study involving 71,094 individuals attended by the health plan. From these, we selected a sample of 123 individuals diagnosed with migraine. For each case, three controls with the same age and sex. We analyze the frequency of use of health services during 12 months (visits, tests, treatments and hospitalizations) by sex and age. The annual costs of health care were compared with the costs of individuals who did not diagnosed with migraine (ICD10-G43). Statistical analysis used OpenEpi software, by calculating the relative and absolute frequencies, means and standard deviation. For statistical significance, Chi-square tests (Mantel-Haenszel and Fisher's Exact), when p<0.05. RESULTS: Of the selected sample diagnosed with migraine, 78.0% were female, with a mean age of 51.3 years and 22.0% male, mean age 58.9 years. In this group, the utilization of health plan was significantly higher than without migraine individuals for visits (p<0.001, OR 2.12), tests (p<0.001; OR 6.60), therapies (p=0.005, OR 1.94), and not significant in hospitalizations (p=0.304). The annual expenditure was US$ 1,531.91 versus US$ 1,220.38 by patients who haven´t migraine (25.5% more). Considering the estimated prevalence and the incremental cost, the annual impact of disease for the health plan was US$ 679,804.92. CONCLUSIONS: As observed, the utilization of outpatient medical services from individuals with migraine was greater than others who do not present, which increases the health care expenses around 25% more.