Stress in the context of the COVID-19 pandemic may have a significant impact on health, including sleep health. Older adults may be particularly vulnerable. This study examined associations between perceived stress and sleep health, mental health, physical health, and overall perceived health outcomes among older adults. We also examined whether specific coping strategies moderate these associations. Older adults (n = 115; M_age = 68.62) reported perceived stress, coping strategies, global sleep quality, depressive symptoms, and perceived mental, physical, and overall health before and during the COVID-19 pandemic. Stress-health relationships were modelled with hierarchical linear regression. Higher perceived stress was associated with greater depressive symptoms and poorer mental health concurrently and longitudinally. Coping strategies moderated the association of perceived stress with physical health and overall perceived health. For example, higher perceived stress was associated with poorer overall perceived health among those with lower problem-focussed coping, but not among those with higher problem-focussed coping. Older adults may benefit from prevention and intervention strategies targeting stress management. Furthermore, identifying people with low problem-focussed coping might be a useful strategy to prevent worsening health in future public health crises.