Unspecified mental disorder (F99) ICD-10-CM
The F99 section covers unspecified mental disorder with 1 ICD-10-CM diagnosis codes, of which 1 are billable in fiscal year 2026. The section is organized into the 1 code ranges listed below.
Code Ranges in This Section 1 ranges · 1 codes
| Code Range | Title | Codes | Billable |
|---|---|---|---|
| F99 | Mental disorder, not otherwise specified (F99) | 1 | 1 |
The info icon previews the code ranges inside each row and its instructional notations from the official Tabular List.
About the F99 Code Range
ICD-10 code F99 is used to classify mental disorders that cannot be specifically diagnosed or do not fit into other defined categories. This code captures a range of mental health issues that are unspecified or lack detailed clinical description.
The code F99 covers conditions commonly referred to as mental disorder not otherwise specified and includes various synonyms like psychiatric behavioral disability, mental disorder during pregnancy, childbirth, and the puerperium, and terms such as mental disorder in mother complicating pregnancy. It helps coders document cases involving complex psychological conditions without clear diagnostic criteria, including culture-bound syndromes, chronic mental disorders, or psychiatric treatments in progress. This code is essential for medical records that indicate general mental health impairment or psychiatric status changes when a definitive diagnosis is pending or unavailable. It supports thorough reporting of miscellaneous or deferred psychiatric conditions, ensuring patients receive appropriate attention even when specific mental health disorders are not confirmed.
Questions About This Page
How many codes are in the F99 range?
The F99 range contains 1 ICD-10-CM diagnosis codes in FY 2026. 1 of them are billable, and the rest are category headers that organize the section.
What conditions does F99 cover?
The range covers unspecified mental disorder. The code ranges listed above break it into groups of related conditions, and each one links to its own page with the full code list.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
