ICD-10 Code F03.A1 – Unspecified dementia, mild, with behavioral disturbance (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code F03.A1 – Unspecified dementia, mild, with behavioral disturbance
What it is
This code identifies mild dementia when the type is not specified and behavioral disturbance is documented. Use it when the record supports dementia with a mild level of impairment and associated behavior changes.
Clinical signs
Clinical features vary; refer to documentation. Mild dementia usually includes noticeable memory or thinking problems with some preserved daily function, plus behavioral symptoms such as agitation, wandering, or mood changes.
When to use this code
Use this code when the provider documents unspecified dementia at a mild stage and also notes behavioral disturbance. It fits encounters where the dementia type is not identified, but the chart clearly supports both severity and behavior-related symptoms.
If the record only says dementia without severity or behavior detail, check documentation before coding. You should not assume behavioral disturbance unless it is explicitly documented or clearly supported in the note.
Do not use for
Do not use this code for dementia without behavioral disturbance, or when the dementia type is specified elsewhere. Check documentation if the stage is moderate or severe, or if the behavior change is not clearly linked to dementia.
Coding tip
Confirm both “mild” severity and “behavioral disturbance” in the provider note before assigning F03.A1.