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F78.A9

F78.A9Other genetic related intellectual disability

Billable / specific codeICD-10-CM

F78.A9 is a billable, specific ICD-10-CM code for other genetic related intellectual disability. It is valid for submission on a claim.

Code also

Both codes may be needed to describe the encounter fully. Sequencing depends on the reason for the visit.

  • , if applicable, any associated disorders

Risk adjustment

F78.A9 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

F78.A9 is named in 9 Medicare coverage policies 7 listing it as supporting medical necessity, and 2 listing it as NOT covered. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

  • A52434Health and Behavior Assessment/Intervention – Medical Policy Articlenot covered
  • A56865Billing and Coding: Psychiatric Inpatient Hospitalizationnot covered
  • A57052Billing and Coding: Psychiatric Inpatient Hospitalization
  • A57053Billing and Coding: Psychiatric Partial Hospitalization Programs

How F78.A9 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to F78.A9.

  • Disability, disabilitiesintellectualautosomal dominant
  • Disability, disabilitiesintellectualautosomal recessive
  • Disability, disabilitiesintellectualgenetic related
  • Disability, disabilitiesintellectualspecified level NEC
  • Disability, disabilitiesintellectualX-linked(syndromic) (Bain type)
  • Disability, disabilitiesintellectualgenetic relatedspecified NEC
  • Disability, disabilitiesintellectualinautosomal dominant mental retardation
  • Disability, disabilitiesintellectualinautosomal recessive mental retardation
  • Disability, disabilitiesintellectualinSATB2-associated syndrome
  • Disability, disabilitiesintellectualinSETBP1 disorder
  • Disability, disabilitiesintellectualinSTXBP1 encephalopathy with epilepsy
  • Disability, disabilitiesintellectualinX-linked mental retardation(syndromic) (Bain type)

Related codes at this level

Codes that share F78.A. If F78.A9 is not quite right, the correct code is usually one of these.

Questions about F78.A9

Is F78.A9 a billable ICD-10-CM code?
Yes. F78.A9 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does F78.A9 sit in the tabular list?
Mental, Behavioral and Neurodevelopmental disorders (F01-F99), in the block Intellectual Disabilities (F70-F79).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.