ICD-10-CM 2027 diagnosis code
F03.CUnspecified dementia, severe
F03.C is a header code, so it can't be reported by itself. Choose one of the 5 more specific codes beneath it.
Code last changed in FY2023 (effective October 1, 2022). Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About F03.C
F03.C is the ICD-10-CM diagnosis code for unspecified dementia, severe. It belongs to category F03 (unspecified dementia), block F01-F09 (mental disorders due to known physiological conditions) and chapter 5 (mental, Behavioral and Neurodevelopmental disorders). It is a header code, so it can't be reported by itself; one of its 5 subcodes must be used instead.
Within F03 (unspecified dementia), F03.C is specifically for unspecified dementia, severe. Related codes cover unspecified severity (F03.9), mild (F03.A) and moderate (F03.B).
To report this condition, pick the subcode that matches the documentation: F03.C0 (without behavioral disturbance, psychotic disturbance, mood disturbance, and anxiety), F03.C1 (with behavioral disturbance), F03.C2 (with psychotic disturbance), F03.C3 (with mood disturbance) and F03.C4 (with anxiety).
It was added in FY2023, effective October 1, 2022.
Specific codes under F03.C
- F03.C0Unspecified dementia, severe, without behavioral disturbance, psychotic disturbance, mood disturbance, and anxietyBillable
- F03.C1Unspecified dementia, severe, with behavioral disturbance
- F03.C2Unspecified dementia, severe, with psychotic disturbanceBillable
- F03.C3Unspecified dementia, severe, with mood disturbanceBillable
- F03.C4Unspecified dementia, severe, with anxietyBillable
Notes that apply from higher levels
Instructions written at a parent level also apply to F03.C.
› From F03 Unspecified dementia
Broader instructions also apply from F01-F09 Mental disorders due to known physiological conditions and Chapter 5: Mental, Behavioral and Neurodevelopmental disorders.
Codes whose notes reference F03.C
- Z91.83Code first
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2023 (effective 10/1/2022): Added
- No changes since FY2023.
Common questions about F03.C
Is F03.C billable?
- No. F03.C is a header code. Report one of its more specific subcodes instead.