F03.9Unspecified dementia, unspecified severity

F03.9 is the ICD-10-CM diagnosis code for unspecified dementia, unspecified severity. It belongs to category F03 (unspecified dementia), block F01-F09 (mental disorders due to known physiological conditions) and chapter 5 (mental, Behavioral and Neurodevelopmental disorders). It is a header code, so it can't be reported by itself; one of its 5 subcodes must be used instead.

Within F03, choose F03.9 (unspecified severity) only when documentation doesn't support a more specific option: mild (F03.A), moderate (F03.B) and severe (F03.C).

To report this condition, pick the subcode that matches the documentation: F03.90 (without behavioral disturbance, psychotic disturbance, mood disturbance, and anxiety), F03.91 (with behavioral disturbance), F03.92 (with psychotic disturbance), F03.93 (with mood disturbance) and F03.94 (with anxiety).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015, and changed in FY2023 (title revised).