Abstract Aims We will first examine whether seeking help for depression and schizophrenia from mental health professionals is nowadays more accepted among the German public than it used to be 30 years ago. Next, we will explore whether changes in help-seeking preferences between 1990 and 2020 are specific to mental health professions or are part of changes in attitudes to professional help-seeking in general. Finally, we will study whether a temporal relationship does exist between the advent of awareness-raising and anti-stigma campaigns after the turn of the millennium and changes in the acceptance of mental health care. Methods In 1990 (n = 2044), 2001 (n = 4005), 2011 (n = 1984) and 2020 (n = 2449) methodologically identical population-based surveys were conducted in Germany. After presentation of an unlabelled case vignette depicting someone with either schizophrenia or depression, we asked about help-seeking recommendations for the person described. Results The German public's readiness to recommend seeking help from mental health professionals has markedly grown over the past 30 years. In contrast, in the eyes of the public, turning to a general practitioner has become only slightly more, consulting a priest even less advisable than it used to be three decades ago. Seeing a naturopath is seen with markedly less disapproval today compared to 1990, but explicit recommendation of this helping source has not increased correspondingly in. The most pronounced increase in the German public's propensity to recommend seeking help from mental health professionals occurred already in the 1990s, i.e. before efforts to heighten public awareness had started. Conclusions Today, the German public is more in favour of mental health professionals than it used to be three decades ago. This seems to be a specific trend, and not to reflecting an increasing propensity towards professional help-seeking in general. Our findings counter the narrative that mental health communication efforts and initiatives have created more favourable attitudes towards mental health care among the public, since the observed changes in attitudes have preceded any campaigns. Instead, we tend to interpret the rise of the popularity of mental health professionals as a reflection of general cultural changes that have taken place over the past decades in Germany, as in other western countries.