OBJECTIVES: Migraine is prevalent, and headache-related disability can impact the ability of migraineurs to work and perform daily activities. This study examined the impact of CM compared to EM on work patterns and productivity across countries. METHODS: Web-based survey data were collected from migraineurs in the US, Canada, Germany, UK, France, Italy, Spain, Australia, and Taiwan. According to ICHD-2 criteria, presence of migraine (past 3-months headaches with pain, nausea, and photophobia/phonophobia) and ≥15 headache days/month indicated CM, and <14 headache days/month indicated EM. Questions on absenteeism and presenteeism (reduced efficiency) in the preceding 4 weeks assessed headache impact on work or school. Linear and logistic regressions, as appropriate, compared migraine group and adjusted for age, gender, race, education, comorbidities, and country. RESULTS: Of 63,001 invitees, 20,987 responded. A total of 9,118 completers (14.5%) comprised the final cohort [n=516 ( Australia) to 1597 (US)]; 83.6% female; 5.5% CM, 90.2% EM. CM respondents were 1.4 times more likely than EM to report that they had missed any work/school due to headache (95% CI=1.1, 1.8). CM reported missing a higher number of work/school days due to headache symptoms than EM (adjusted mean±SE=8.83±0.59 vs. 4.05±0.44, p<0.0001), as well as working more days with headache symptoms (16.97±0.54 vs. 5.38±0.39, p<0.0001). CM also missed more days due to illnesses other than headache than EM participants (13.66±1.98 vs. 9.33±1.42, p<0.01). CM and EM reported working at about half of their full effectiveness with headache symptoms (p>0.05). CM reported experiencing more impairment on work ability or activity than EM (CM=31.1%, EM=24.4%), or requiring more bed rest (CM=33.5%, EM=26.2%) when experiencing severe headaches. CONCLUSIONS: Migraine adversely affected presenteeism and increased absenteeism of migraine sufferers, particularly among those with CM, who missed more days and worked more days with headache than EM.