Abstract: A growing number of studies have examined alcohol use during the COVID-19 pandemic. However, few longitudinal studies evaluated the prevalence and correlates of different trajectories of problematic alcohol use in vulnerable segments of the population, such as US veterans, over the 3-year course of the COVID-19 pandemic. Data were analyzed from the National Health and Resilience in Veterans Study, a nationally representative, longitudinal study of 2,441 US veterans. Latent growth mixture modeling was used to identify the trajectories and correlates of problematic alcohol use. Four trajectories were identified: consistent (N = 170, weighted 7.2%), decreasing (N = 38, weighted 2.2%), increasing (N = 22, weighted 1.2%), and low (N = 2,211, weighted 89.4%) problematic alcohol use. Greater household income, pre-pandemic drug use disorder (DUD), lower social support, and COVID-19 infection to self or non-household members were associated with an increasing relative to decreasing problematic alcohol use trajectory. Greater household income, adverse childhood experiences (ACEs), pre-pandemic DUD, lower social support, and greater COVID-related social restriction stress were associated with an increasing relative to a low problematic alcohol use trajectory. Younger age, male sex, ACEs, pre-pandemic DUD, lower pre-pandemic and greater decline in protective psychosocial characteristics, COVID-19 infection to non-household member, and lower COVID-related financial stress were associated with a consistent relative to a low problematic alcohol use trajectory. Overall, pre-pandemic greater income, DUD, and lower social support were associated with an increase in problematic alcohol use among US veterans during the COVID-19 pandemic. Results may help inform prevention efforts to mitigate problematic alcohol use during prolonged crises in this population.