We used Cluster Analysis of Migraine-associated Symptoms (CAMS) to critically evaluate current International Classification of Headache Disorders-Third Edition (ICHD-3) migraine-associated symptoms criteria. Diagnostic criteria play a central role in guiding clinical trial inclusion, and therefore available treatments. Migraine and tension-type headaches (TTH) are differentiated in ICHD-3 by many headache characteristics, including associated symptoms. A diagnosis of probable migraine indicates some but not all features of migraine are met. Photophobia and phonophobia, or nausea and/or vomiting, are required to meet a diagnosis of migraine; however, CAMS-a model that describes associated symptoms across youth with headache-indicates that a broader range of symptoms contain information about migraine burden. In this multisite retrospective cross-sectional study, we evaluated ICHD-3 migraine criteria. Youth aged 6-17 years with migraine (including probable migraine) or TTH were included in the analysis. We used CAMS to evaluate the migraine-associated symptom criterion. With CAMS as a guide, we evaluated how changes to the migraine-associated symptom criterion altered who met the diagnosis of migraine. Of the 9017 participants included in this study, 66.7% were female and had a median (interquartile range) age of 13 (10-15) years. Most participants had migraine or probable migraine (99.0%), and the remainder had TTH (1.0%). A sizable percentage (10.1%) of youth under the umbrella diagnosis of migraine were diagnosed with probable migraine because they did not meet migraine-associated symptom criterion D; however, many in this group reported several non-ICHD migraine-associated symptoms. We explored alterations to criterion D based on CAMS. Allowing for photophobia or phonophobia re-categorized 55.6% of youth as having migraine, though some only had one symptom. Including lightheadedness or lightheadedness and spinning re-categorized 19.7% and 25.8% of youth with migraine, respectively, but all of those who were re-categorized had at least two migraine-associated symptoms. The ICHD-3 captures the most prevalent migraine-associated symptoms; however, many youths with probable migraine who do not meet full criteria due to insufficient associated symptoms nonetheless experience multiple non-ICHD migraine-associated symptoms. Changes to criterion D should be considered for the ICHD-4.