Although the COVID-19 pandemic caused significant stress and anxiety among many people, individuals’ experiences varied. We examined whether specific forms of anxiety predicted distinct trajectories of anxiety, perceived stress, and COVID-related worries during 3 early months of the pandemic. In a longitudinal study ( N = 291), adolescents’ ( n = 194) social anxiety and generalized anxiety levels were assessed via parent reports and self-reports and clinical diagnostic interviews. Later, when these adolescents were young adults ( n = 164), anxiety, stress, and COVID-related worries were assessed thrice during the pandemic. Prepandemic generalized anxiety predicted higher initial levels and maintenance of anxiety, stress, and COVID-related worries during the pandemic. In contrast, prepandemic social anxiety predicted lower initial levels of anxiety, stress, and COVID-related worries, but this initial effect on anxiety and stress was offset over time by social anxiety’s positive effect on the slope. Our results highlight the importance of understanding how prepandemic factors influence individuals’ experiences during the pandemic.