F09 vs F29
F09 (Unspecified mental disorder due to known physiological condition) compared with F29 (Unspecified psychosis not due to a substance or known physiological condition), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. F09 carries an Excludes1 note covering F29: “psychosis NOS (F29)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
No — do not report together. F29 carries an Excludes1 note covering F09: “unspecified mental disorder due to known physiological condition (F09)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| F09Unspecified mental disorder due to known physiological condition | F29Unspecified psychosis not due to a substance or known physiological condition | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | F01-F99 — Mental, Behavioral and Neurodevelopmental Disorders (F01-F99) | F01-F99 — Mental, Behavioral and Neurodevelopmental Disorders (F01-F99) |
| Definition | Unspecified mental disorder due to known physiological condition is a billable ICD-10-CM diagnosis code (F09). | Unspecified psychosis not due to a substance or known physiological condition is a billable ICD-10-CM diagnosis code (F29). |
| Includes | Mental disorder NOS due to known physiological condition Organic brain syndrome NOS Organic mental disorder NOS Organic psychosis NOS | Psychosis NOS Unspecified schizophrenia spectrum and other psychotic disorder |
| Code first | the underlying physiological condition | — |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources