F91.9 — Conduct disorder, unspecified
Is F91.9 billable?
Yes, but F91.9 is an unspecified code. F91.9 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, F91.9 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting F91.9 — the more specific alternatives are listed below.
F91.9 at a glance
| Code | F91.9 |
|---|---|
| Description | Conduct disorder, unspecified |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does F91.9 group to?
F91.9 sits in MDC 19 and helps define the logic of 1 MS-DRG (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 886Behavioral and Developmental Disordersmedical
How is F91.9 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to F91.9. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Disorder › conduct (of)
- Disorder › disruptive (of)
- Disturbance › conduct (s)
- Disturbance › conduct › disruptive (s)
Inclusion terms
Alternative wording in documentation that is classified to F91.9.
- Behavioral disorder NOS
- Conduct disorder NOS
- Disruptive behavior disorder NOS
- Disruptive disorder NOS
Excludes1 — never code together — inherited from F91
The conditions below can never be reported together with F91.9 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Excludes2 — not included here — inherited from Chapter 5
The conditions below are not part of F91.9, but a patient may have both at the same time. When documentation supports it, F91.9 and the excluded code may both be reported.
- symptoms, signs and abnormal clinical laboratory findings, not elsewhere classified (R00-R99)
Excludes2 — not included here — inherited from F91
The conditions below are not part of F91.9, but a patient may have both at the same time. When documentation supports it, F91.9 and the excluded code may both be reported.
How long has F91.9 existed?
F91.9 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.