Cost-effectiveness and cost per successful treatment has been evaluated in 186 outpatients randomised to treat moderate to severe migraine attacks either with subcutaneous sumatriptan 6 mg (n = 97) or with their current therapy (n = 89) during an open, multicentre study of 3 months. Within 2 hours, headache severity decreased to none/mild in 86% of all attacks in the sumatriptan group (STG) compared to 25% in the customary group (CTG). Migraine was alleviated earlier in the STG than in the CTG (median 3.78 vs. 13.39 hours, p < 0.0001). The direct and total cost of treatment was 133 and 2012 BF, respectively, in the CTG and 1400 and 2522 BF, respectively, in the STG. Measuring the effectiveness of earlier pain relief with sumatriptan, the incremental cost-effective ratios for direct and total cost were 132 and 53 BF per hour of relieved pain, respectively. For this price, significantly more sumatriptan patients improved their quality of life by more than 20% (61.6 vs. 20.6% patients, p < 0.001) and less sumatriptan patient consulted a medical professional (11.3 vs. 29.2% patients, p < 0.01), used less medication for adverse events (6.2 vs. 22.5%, p < 0.001) and suffered less from associated migraine symptoms. The median number of hours of diminished work-efficiency (3 vs. 7 hours, p < 0.01) or of suspension of non-professional activity (10 vs. 24 hours, p < 0.001) was also significantly lower in the STG. The total cost per successfully treated patient was lower in the STG. Sumatriptan is more effective, provides a better quality of life, reduces health care resource utilisation, and improves work productivity as compared to the CTG, thereby resulting in a favourable cost-effectiveness ratio.