F20.3 is the authoritative medical code for Undifferentiated schizophrenia. This classification is used in medical billing and clinical recording to specify the clinical criteria for undifferentiated schizophrenia (ICD-10-CM F20.3), ensuring healthcare documentation aligns with 2026 federal coding standards.
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Official Registry Overview & Definition
Undifferentiated schizophrenia is a billable ICD-10-CM diagnosis code F20.3. Inclusion terms: Atypical schizophrenia. Excludes1 (not coded here): acute schizophrenia-like psychotic disorder F23; brief psychotic disorder F23; cyclic schizophrenia F25.0; mood affective disorders with psychotic symptoms (F30.2, F31.2, F31.5, F31.64, F32.3, F33.3); schizoaffective disorder F25.-; schizophrenic reaction NOS F23. Excludes2 (not included here): post-schizophrenic depression F32.89; schizophrenic reaction in:; alcoholism (F10.15-, F10.25-, F10.95-); brain disease F06.2; epilepsy F06.2; psychoactive drug use (F11-F19 with .15. .25, .95); schizotypal disorder F21. Use additional code: code, if applicable, to identify:; other specified cognitive deficit R41.84-.
Official Tabular Instructional Notes
Sequencing, inclusion, and exclusion notes published for F20.3 in the official ICD-10-CM tabular list.
Inclusion Terms
Alternative terms the tabular list files under this code.
Excludes1 — Not Coded Here
Conditions that can never be reported with this code; the two are mutually exclusive.
- acute schizophrenia-like psychotic disorder F23
- brief psychotic disorder F23
- cyclic schizophrenia F25.0
- mood affective disorders with psychotic symptoms (F30.2, F31.2, F31.5, F31.64, F32.3, F33.3)
- schizoaffective disorder F25.-
- schizophrenic reaction NOS F23
Excludes2 — Not Included Here
Conditions not covered by this code, but which may be reported alongside it when both are present.
- post-schizophrenic depression F32.89
- schizophrenic reaction in:
- alcoholism (F10.15-, F10.25-, F10.95-)
- brain disease F06.2
- epilepsy F06.2
- psychoactive drug use (F11-F19 with .15. .25, .95)
- schizotypal disorder F21
Use Additional Code
Supplementary codes the tabular list directs you to add.
- code, if applicable, to identify:
- other specified cognitive deficit R41.84-
Frequently Asked Questions (FAQ) & Clinical Guidance
What can't be coded together with F20.3?
Per Excludes1 instructions, F20.3 must not be reported with: acute schizophrenia-like psychotic disorder (F23); brief psychotic disorder (F23); cyclic schizophrenia (F25.0); mood [affective] disorders with psychotic symptoms (F30.2, F31.2, F31.5, F31.64, F32.3, F33.3).
Can F20.3 be reported alongside related conditions?
Per Excludes2 instructions, F20.3 and the following may both be reported when both are present: post-schizophrenic depression (F32.89); schizophrenic reaction in:; alcoholism (F10.15-, F10.25-, F10.95-); brain disease (F06.2).
Is an additional code needed with F20.3?
Use additional code(s) to specify: code, if applicable, to identify:; other specified cognitive deficit (R41.84-).
What conditions are included under F20.3?
Undifferentiated schizophrenia includes: Atypical schizophrenia.
Codes in This Family (10)
Official ICD-10-CM classifications in the same code family as F20.3, with their registry titles.
- F20 — Schizophrenia
- F20-F29 — Schizophrenia, schizotypal, delusional, and other non-mood psychotic disorders (F20-F29)
- F20.0 — Paranoid schizophrenia
- F20.1 — Disorganized schizophrenia
- F20.2 — Catatonic schizophrenia
- F20.5 — Residual schizophrenia
- F20.8 — Other schizophrenia
- F20.81 — Schizophreniform disorder
- F20.89 — Other schizophrenia
- F20.9 — Schizophrenia, unspecified
Indexed Clinical Terms (2)
Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code.
- Schizophrenia, schizophrenic, atypical (form)
- Schizophrenia, schizophrenic, undifferentiated (type)
Related Codes & Numerical Sequence (Crawl Map)
Search engines and indexers are advised to traverse adjacent medical codes in this sub-chapter range to find correlated diagnoses or therapeutic procedures: