F03.C18 – Unspecified dementia, severe, with other behavioral disturbance

ICD-10-CM 2027 diagnosis code · Mental disorders due to known physiological conditions

Billable code

ICD-10-CM code F03.C18

Code: F03.C18 (claims format: F03C18)
Description: Unspecified dementia, severe, with other behavioral disturbance
Short description: Unspecified dementia, severe, with other behavioral disturb
Billable: Yes – valid for HIPAA-covered transactions
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 5. Mental, Behavioral and Neurodevelopmental disorders (F01-F99)
Block: F01-F09 Mental disorders due to known physiological conditions
Parent codes: F03 › F03.C › F03.C1

Notes for F03.C18

Applicable to:

Unspecified dementia, severe, with behavioral disturbances such as sleep disturbance, social disinhibition, or sexual disinhibition

Use additional code:

code, if applicable, to identify wandering in unspecified dementia (Z91.83)

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

F03 – Unspecified dementia

Applicable to:

Major neurocognitive disorder NOS
Presenile dementia NOS
Presenile psychosis NOS
Primary degenerative dementia NOS
Senile dementia NOS
Senile dementia depressed or paranoid type
Senile psychosis NOS

Excludes2 (not included here):

dementia with delirium or acute confusional state (F05)
mild memory disturbance due to known physiological condition (F06.8)

Block F01-F09

Notes:

This block comprises a range of mental disorders grouped together on the basis of their having in common a demonstrable etiology in cerebral disease, brain injury, or other insult leading to cerebral dysfunction. The dysfunction may be primary, as in diseases, injuries, and insults that affect the brain directly and selectively; or secondary, as in systemic diseases and disorders that attack the brain only as one of the multiple organs or systems of the body that are involved.

Index terms for F03.C18

Entries in the ICD-10-CM alphabetic index that lead to this code:

Related codes in F03.C1

F03.C11 – Unspecified dementia, severe, with agitationBillable

Frequently asked questions

What is ICD-10 code F03.C18?

F03.C18 is the ICD-10-CM code for unspecified dementia, severe, with other behavioral disturbance, in the block F01-F09 (Mental disorders due to known physiological conditions).

Is F03.C18 a billable code?

Yes. F03.C18 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.

What category does F03.C18 belong to?

It belongs to category F03 – Unspecified dementia.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.