The COVID-19 pandemic has been observed to negatively affect older adults' psychological health compared with prepandemic levels. However, older adults' coping efficacy may differ depending on their age, and little is known about effects of fluctuations in pandemic severity. Two longitudinal studies tested the hypothesis that pandemic severity would affect psychological health and be moderated by age. In Study 1 (N = 111), older adults (aged 62-96) were assessed semiannually before and after the first United States COVID-19 case over up to 10 years. Depressive symptoms and stress, but not cognitive difficulties, were higher during COVID-19; pandemic severity had little effect. Estimated increases were smaller for a 65-year-old than for an 85-year-old. In Study 2 (N = 221), older adults (aged 51-95) were assessed weekly over up to 8 weeks during the COVID-19 pandemic. Higher national pandemic severity was associated with more cognitive difficulties, more depressive symptoms, and more stress. In an opposite pattern from Study 1, estimated increases were larger for a 65-year-old than for an 85-year-old. Old-old adults might be most susceptible to long-term psychological effects of the pandemic era, as in Study 1, but more resilient to short-term effects, as in Study 2. Coping strategies associated with increasing age may be less efficacious for more chronic and severe problems. Conversely, the same coping strategies may be more efficacious for shorter, less severe problems. Differentiating between reactivity to longer term and shorter term pandemic stressors can identify the most resilient or vulnerable ages within older adulthood. (PsycInfo Database Record (c) 2023 APA, all rights reserved).