The aim was to clarify the prevalence and correlates of probable major depressive disorder and probable generalized anxiety disorder in the general adult population during the COVID-19 pandemic. Data were derived from a nationally representative survey (August and September 2021). In total, n = 3075 individuals took part. To quantify probable generalized anxiety disorder, the established Generalized Anxiety Disorder-7 (GAD-7; cutoff of 10) was used. Moreover, the Patient Health Questionnaire-9 (PHQ-9; cutoff of 10) was used to quantify probable major depressive disorder. The prevalence of probable major depressive disorder was 20.0% and the prevalence of probable generalized anxiety disorder was 13.4%. Particularly high prevalence rates were observed for younger individuals, individuals with migration background and individuals with at least one chronic disease. The likelihood of probable major depressive disorder was positively associated with younger age, being unmarried, having a migration background, smoking, daily alcohol intake, the presence of chronic diseases and lower self-rated health. Similarly, the likelihood of probable generalized anxiety disorder was positively associated with younger age, being unmarried, smoking, the presence of chronic diseases and lower self-rated health. In conclusion, the magnitude of probable major depressive disorder and probable generalized anxiety disorder in Germany in late summer of 2021 was highlighted. Identifying the correlates of them may help to tackle individuals at higher risk.