Unspecified intellectual disabilities (F79) ICD-10-CM
The F79 code range covers unspecified intellectual disabilities with 1 ICD-10-CM diagnosis codes. 1 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Inclusion Terms
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
- Mental deficiency NOS
- Mental subnormality NOS
Codes in the F79 Range 1 codes · 1 billable
- F79 Unspecified intellectual disabilities
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the F79 range.
Arachnodactyly
An abnormal bone development that is characterized by extra long and slender hands and fingers, such that the clenched thumb extends beyond the ulnar side of the hand. Arachnodactyly can include feet and toes. Arachnodactyly has been associated with several gene mutations and syndromes.
Hypertelorism
Abnormal increase in the interorbital distance due to overdevelopment of the lesser wings of the sphenoid.
Intellectual Disability
Subnormal intellectual functioning which originates during the developmental period. This has multiple potential etiologies, including genetic defects and perinatal insults. Intelligence quotient (IQ) scores are commonly used to determine whether an individual has an intellectual disability. IQ scores between 70 and 79 are in the borderline range. Scores below 67 are in the disabled range. (from Joynt, Clinical Neurology, 1992, Ch55, p28)
WAGR Syndrome
A contiguous gene syndrome associated with hemizygous deletions of chromosome region 11p13. The condition is marked by the combination of WILMS TUMOR; ANIRIDIA; GENITOURINARY ABNORMALITIES; and INTELLECTUAL DISABILITY.
X-Linked Intellectual Disability
A class of genetic disorders resulting in INTELLECTUAL DISABILITY that is associated either with mutations of GENES located on the X CHROMOSOME or aberrations in the structure of the X chromosome (SEX CHROMOSOME ABERRATIONS).
About the F79 Code Range
The ICD-10 code F79 is used to classify cases of unspecified intellectual disabilities when a precise diagnosis or cause is not identified. This code helps document intellectual functioning impairment that does not fit more specific categories.
Intellectual disabilities under F79 may be connected to various underlying conditions often described by synonyms such as intellectual functioning disability, low intelligence, below average intellect, or complex syndromes involving neurological, skeletal, or developmental abnormalities. For medical coders and healthcare professionals, recognizing that terms like intellectual disability syndrome, congenital heart disease with intellectual disability, or developmental delay with intellectual disability may all be encompassed under this unspecified category aids accurate use of the ICD-10 code. This code captures intellectual disabilities when the precise etiology—such as genetic syndromes, brain malformations, or metabolic issues—is unknown or not specified in records.
Questions About This Page
How many billable codes are in the F79 range?
Of the 1 codes in this range, 1 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the F79 range classify?
The range classifies unspecified intellectual disabilities. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
