A systematic review and a meta-analysis were conducted to examine the overall prevalence of psychological health outcomes during COVID-19. Seven databases were systematically searched to include studies reporting on at least one psychological outcome. The pooled prevalence of primary psychological outcomes was 26% (95%CI: 21–32). Pooled prevalence for symptoms of PTSD was 33% (0–86), anxiety 28% (21–36), stress 27% (14–43), and depression 22% (13–33). The prevalence of psychological outcomes was similar in healthcare workers and in the general population (34% [24–44] and 33% [27–40] respectively). High prevalence figures support the importance of ensuring adequate provision of resources for mental health.