Dissociative Identity Disorder is often described as extremely rare, but research does not fully support that claim. Most current studies estimate the prevalence of DID in the general population to be between 0.1% and 2%, with some studies suggesting it may be as high as 3–5%. According to the DSM-5-TR, the 12-month prevalence in a small U.S. community sample was 1.5%, and a lifetime prevalence study of Turkish women found a rate of 1.1%.

In general population studies using dissociation-specific screening tools, prevalence rates typically range from 0.8% to 1.5%. Dissociative disorders as a whole are more common, ranging from 3% to 18.3% depending on the study.

DID appears more frequently in clinical settings. Studies show that it affects about 6–10% of psychiatric inpatients and about 6% of psychiatric outpatients. Research involving college students has also found notable rates, with 3.7% meeting criteria for DID and even higher percentages showing elevated dissociative symptoms.

Gender differences in diagnosis are debated. Some studies suggest DID is more commonly diagnosed in females, while others find similar rates between males and females. Differences may be related to underreporting, stigma, incarceration rates, or reduced help-seeking among men.

DID is not limited to one culture or country. Although prevalence rates vary somewhat across nations, epidemiological studies still estimate rates around 1.1–1.5% worldwide, suggesting that DID is culturally present across different populations rather than confined to a specific group.

When compared to other mental disorders, DID is about as common as chronic major depressive disorder and obsessive-compulsive disorder, and it is more common than schizophrenia. This comparison shows that DID is not as rare as many people believe.