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Background: Studying the safety of travel vaccines poses challenges since recipients may be traveling during the risk window for adverse events and the identification of a suitable comparison group can also be difficult. The examination of traveler characteristics, travel vaccination patterns, and health care uti-lization using electronic health record (EHR) data can inform the feasibility of future travel vaccine safety studies.Methods: A retrospective cohort study of health plan members in the Vaccine Safety Datalink Project aged 9 months and older who had a travel-related encounter or received a travel vaccine from 2009 to 2018 was performed. Travel regions visited, travel duration, type of travel vaccine received (typhoid, yel-low fever, Japanese encephalitis, rabies, and cholera), and timing of vaccination date before departure date were described. Sociodemographic information, clinical characteristics, and health care utilization were compared between travelers who received travel vaccines and travelers who did not.Results: A total of 1,026,822 unique travelers departing from the United States were identified; 612,795 travelers received 898,196 doses of travel vaccines. The most commonly administered travel vaccine was typhoid vaccine and 77% of all travel vaccines were given more than one week prior to departure. Compared with travelers without travel vaccines, travelers with travel vaccines were overall similar but as a group were slightly younger, healthier, and had lower Hispanic representation. Health care uti-lization dramatically decreased during travel. Outpatient visits decreased from 294.8 visits per 10,000 person-days before travel to 24.2 visits per 10,000 person-days during reported travel dates.Conclusions: Through the EHR information from almost a million travelers, a departure date and duration of travel were successfully captured for the majority of travelers with corresponding health care utiliza-tion data. Time after vaccination and prior to departure can potentially be used in the future to compare travelers who receive travel vaccines with travelers who do not receive travel vaccines when looking at adverse events of interest after vaccination.(c) 2022 The Authors. Published by Elsevier Ltd.