Objective: While a substantial body of research describes the disabling impacts of migraine attacks, less research has described the impacts of migraine on physical functioning between migraine attacks. The objective of this study is to describe physical impairment during and between migraine attacks as a dimension of burden experienced by people living with chronic migraine., Methods: The physical impairment domain of the Migraine Physical Function Impact Diary was recorded in headache diaries from the Medication Overuse Treatment Strategy trial. Days with moderate to severe headache were used to approximate migraine attacks. Factor analysis and regression analysis were used to describe associations between migraine and physical impairment., Results: 77,662 headache diary entries from 720 participants were analyzed, including 25,414 days with moderate to severe headache, 19,149 days with mild headache, and 33,099 days with no headache. Mean physical impairment score was 41.5 (SD = 26.1) on days with moderate to severe headache, 12.8 (SD = 15.0) on days with mild headache, and 5.2 (SD = 13.1) on days with no headache. Physical impairment on days with mild headache and days with no headache was significantly associated with days since last moderate to severe headache, physical impairment with last moderate to severe headache, mild headache (compared to no headache), depression, hypersensitivities and cranial autonomic symptoms., Conclusions: Physical impairment occurs on migraine and non-migraine days. Study participants with frequent headaches, symptoms of depression, hypersensitivities and cranial autonomic symptoms experience physical impairment at a higher rate on days with no headache and days with mild headache. Clinical Trial Registration: ClinicalTrials.gov (NCT02764320)., Competing Interests: Declaration of conflicting interestsThe authors declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: DJW reports nothing to disclose. GMD reports grants from the American Brain Foundation/American Academy of Neurology and Amgen. JGH reports grants from the Patient Centered Outcomes Research Institute (PCORI). DWD reports personal fees from Amgen, Atria, CapiThera Ltd., Cerecin, Ceruvia Lifesciences LLC, CoolTech, Ctrl M, Allergan, AbbVie, Biohaven, GlaxoSmithKline, Lundbeck, Eli Lilly, Novartis, Impel, Satsuma, Theranica, WL Gore, Genentech, Nocira, Perfood, Praxis, AYYA Biosciences, Revance, and Pfizer. He has received speaking fees from from Teva, Amgen, Eli Lilly, Lundbeck, and Pfizer and honoraria from American Academy of Neurology, Headache Cooperative of the Pacific, Canadian Headache Society, MF Med Ed Research, Biopharm Communications, CEA Group Holding Company (Clinical Education Alliance LLC), Vector Psychometric Group, Clinical Care Solutions, CME Outfitters, Curry Rockefeller Group, DeepBench, Global Access Meetings, KLJ Associates, Academy for Continued Healthcare Learning, Majallin LLC, Medlogix Communications, Medica Communications LLC, MJH Lifesciences, Miller Medical Communications, WebMD Health/Medscape, Wolters Kluwer Health, Oxford University Press, Cambridge University. He has stock or stock options in Ctrl M, Aural Analytics, Axon Therapeutics, ExSano, Palion, Man and Science, Healint, Theranica, Second Opinion/Mobile Health, Epien, Nocira, Matterhorn, Ontologics, King-Devick Technologies, Precon Health, Ayya Biosciences, Cephalgia Group, Atria Health. He sits on the board of directors for Epien, Matterhorn, Ontologics, King-Devick Technologies, Precon Health, Axon Therapeutics, and Cephalgia Group. He has received research support from United States Department of Defense, National Institutes of Health, Henry Jackson Foundation, Sperling Foundation, American Migraine Foundation, and Patient Centered Outcomes Research Institute (PCORI). He holds Patent 17189376.1-1466:vTitle: Botulinum Toxin Dosage Regimen for Chronic Migraine Prophylaxis without fee and has submitted a patent application for Synaquell® (Precon Health). TJS reports a grant from PCORI during the conduct of the MOTS Trial; grants from Amgen, American Migraine Foundation, United States Department of Defense, National Institutes of Health, American Heart Association, Spark Neuro, and Henry Jackson Foundation, personal fees from Abbvie, Allergan, Amgen, Axsome, Biodelivery Science, Biohaven, Click Therapeutics, Collegium, Eli Lilly, Ipsen, Linpharma, Lundbeck, Novartis, Satsuma, Theranica, Tonix, and Scilex. He has submitted a patent application for predicting speech outcomes in post-traumatic headache and migraine. He reports stock options from Aural Analytics and Nocira and royalties from Up To Date.