Service members are at risk for unintentional drownings or near drownings during training, occupational activities, and off-duty recreation. During 2013-2017, there were 359 incident accidental drowning episodes (includes drownings and near drownings) for a crude rate of 5.7 cases per 100,000 person-years. Compared with their respective counterparts, the overall incidence rates of drowning episodes were highest among males, those aged 29 years or younger, those who were unmarried, and enlisted service members. Across the services, crude overall rates were highest among Marine Corps and Navy members and lowest among Air Force members. Overall rates of drowning episodes were highest among those working in motor transport and lowest among those in repair/engineering or communications/intelligence occupations. The overall rate of drowning episodes among service members with any history of alcohol-related disorder was nearly twice that of those without any history of alcohol-related disorder. Between 2015 and 2017, annual rates of drowning episodes decreased in each service, with the greatest decline observed among Navy and Marine Corps members. The results of this report may be useful to increase awareness regarding the ongoing risks and effects of drowning episodes among U.S. service members.