We sent an anonymous self-administered questionnaire to 4200 employees of a Trust hospital, 1903 of whom returned it. We identified 158 migraine sufferers according to International Headache Society (IHS) criteria. These sufferers estimated 2.0 days/year absence from work, and an equivalent of 5.5 days/year lost by reduced effectiveness at work, caused by their migraine at an estimated financial cost of over 50,000 pounds to the Trust. An additional 220 individuals who had received a diagnosis of migraine from a doctor but fulfilled only 3/4 IHS criteria lost the equivalent of 6.7 days off work at a further cost of 63,000 pounds). Few patients had consulted their general practitioner about their migraines in the last 3 months. Most (78%) were using only over-the-counter medication. Migraine patients should be encouraged to seek medical attention.