Importance: Stigma, the prejudice and discrimination attached to mental illness, has been persistent, interfering with help-seeking, recovery, treatment resources, workforce development, and societal productivity in individuals with mental illness. However, studies assessing changes in public perceptions of mental illness have been limited.

Question: What changes in the prejudice and discrimination attached to mental illness have occurred in the past 2 decades?

Findings: In this survey study of 4129 adults in the US, survey data from 1996 to 2006 showed improvements in public beliefs about the causes of schizophrenia and alcohol dependence, and data from a 2018 survey noted decreased rejection for depression. Changes in mental illness stigma appeared to be largely associated with age and generational shifts.

Meaning: Results of this study suggest a decrease in the stigma regarding depression; however, increases and stabilized attributions regarding the other disorders may need to be addressed.