ICD-10 F91.9
Billable / SpecificConduct disorder, unspecified
About ICD-10-CM F91.9
ICD-10-CM code F91.9 represents Conduct disorder, unspecified. This is a billable/specific code in the Mental, Behavioral, and Neurodevelopmental chapter (block F91). The 2026 edition of ICD-10-CM F91.9 became effective on October 1, 2025.
Inclusion Terms / Approximate Synonyms
Clinical terms and conditions classified under F91.9. Per CMS ICD-10-CM Tabular 2026.
- Behavioral disorder NOS
- Conduct disorder NOS
- Disruptive behavior disorder NOS
- Disruptive disorder NOS
Medicare LCD Coverage for F91.9
Local Coverage Determinations (LCDs) from CMS MACs that list F91.9 as a covered diagnosis.
Showing top 10 of 112 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing F91.9.
1 Aetna
1 Cigna
4 Medicare
CPT Codes Commonly Billed with F91.9
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
- 90847 Family psychotherapy with patient — anxiety, depression, adjustment, relationship problems, substance use, eating disorder, conduct disorder, separation anxiety Psychiatry
Convert F91.9 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| F91.9 | 3129 | 00000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To F91.9
Other codes in section F90-F98 (Behavioral and emotional disorders with onset usually occurring in childhood and adolescence).
ICD-10 F91.9, Billing FAQ
Is ICD-10 code F91.9 billable? +
Yes, F91.9 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What other names or terms map to F91.9? +
ICD-10 F91.9 includes: Behavioral disorder NOS; Conduct disorder NOS; Disruptive behavior disorder NOS, and 1 more clinical synonyms.
What CPT codes are commonly billed with F91.9? +
Procedures frequently paired with F91.9 include: 90847.
What ICD-9 codes does F91.9 map to? +
Per CMS GEMs, F91.9 maps to ICD-9 codes: 3129. Useful for legacy data review and historical claim analysis.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on June 1, 2026.
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