F29
BillableUnspecified psychosis not due to a substance or known physiological condition
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is F29 an HCC code?
Yes. F29 maps to Delusional and Other Specified Psychotic Disorders under the CMS-HCC V28 risk adjustment model (and Reactive and Unspecified Psychosis under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for F29
For F29to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed F29 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
F29 is the ICD-10-CM diagnosis code for unspecified psychosis not due to a substance or known physiological condition. This code describes a mental health condition where a person experiences psychotic symptoms (such as hallucinations, delusions, or disorganized thinking) that cannot be attributed to drug use, alcohol, or a known medical condition. It is used when the specific type of psychosis cannot be determined or classified more precisely. F29 sits in the ICD-10-CM chapter for mental, behavioral and neurodevelopmental disorders (f01-f99), within the section covering schizophrenia, schizotypal, delusional, and other non-mood psychotic disorders (f20-f29).
Under the CMS-HCC V28 risk adjustment model, F29 maps to Delusional and Other Specified Psychotic Disorders (HCC 152) with a community, non-dual, aged base RAF weight of 0.546. Under the older CMS-HCC V24 model, F29 maps to Reactive and Unspecified Psychosis (HCC 58) with a community, non-dual, aged base RAF weight of 0.508. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
Use F29 only when psychosis is documented but the underlying cause is unclear or cannot be specified; always investigate and document whether symptoms are related to substance use, medical conditions, or other psychotic disorders before assigning this code. Because F29 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for F29 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Use F29 only when psychosis is documented but the underlying cause is unclear or cannot be specified; always investigate and document whether symptoms are related to substance use, medical conditions, or other psychotic disorders before assigning this code
- •This is a non-specific code; attempt to obtain more detailed clinical information to assign a more specific psychotic disorder code (such as F20-F28 range) when possible, as F29 may trigger additional documentation requests from payers
Clinical Significance
Unspecified psychosis not due to a substance or known physiological condition is used when a patient has documented psychotic symptoms but the specific type of psychotic disorder cannot be determined. This is often an early or provisional diagnosis used during initial evaluation. While it captures a high-value HCC, clinical best practice calls for working toward a more specific diagnosis (schizophrenia, delusional disorder, etc.) as the clinical picture clarifies over time.
Documentation Requirements
- ✓Documentation of psychotic symptoms (hallucinations, delusions, disorganized thinking/behavior)
- ✓Assessment by a qualified mental health professional
- ✓Documentation that substance-induced and medical causes have been considered or ruled out
- ✓Explanation of why a more specific psychotic disorder diagnosis cannot yet be assigned
- ✓Plan for ongoing evaluation to refine the diagnosis over time
- ✓Current treatment plan including any antipsychotic medications
Excludes 1 — Do NOT code together
Commonly Confused Codes
- •F28 — OTHER specified psychotic disorder indicates a specific type was identified; F29 means the type is undetermined
- •F20.9 — Schizophrenia, unspecified requires meeting schizophrenia criteria; F29 has not reached that diagnostic conclusion
- •F23 — Brief psychotic disorder should be used when symptoms resolve within one month
- •F06.2 — Psychotic disorder due to medical condition should be used when a medical cause is identified
- •R44.3 — Hallucinations, unspecified is a symptom code, not a diagnosis; use F29 when a psychotic disorder diagnosis is established