Dementia ICD-10 Codes: Types, Severity, Documentation & Billing Guidelines

Choosing the correct dementia ICD-10 code involves more than identifying memory loss or cognitive decline. Healthcare providers must document the type of dementia, its severity, associated disturbances, and any underlying condition that affects diagnosis coding.

A code such as F03.90 would be used for unspecified dementia which has no severity or specific disturbances. Vascular dementia, Alzheimer’s disease and dementia with agitation will have separate codes.

Around 7.4 million Americans aged 65 and above suffer from clinical Alzheimer’s dementia (2026 Alzheimer’s Disease Facts and Figures). With increasing numbers of patients receiving cognitive care, it is important to accurately record dementia to ensure accurate medical billing.

This article covers dementia ICD-10 codes, vascular dementia codes, what needs to be documented, Medicare billing and some common mistakes made when claiming.

What Is the ICD-10 Code for Dementia?

F03.90 is the ICD-10-CM code for unspecified dementia, unspecified severity, without behavioral disturbance, psychotic disturbance, mood disturbance, or anxiety.

The correct category depends on the provider’s documented diagnosis.

Common Dementia ICD-10 Codes

ICD-10 code	Description
F03.90	Unspecified dementia without specified disturbances
F03.911	Unspecified dementia with agitation
F03.918	Unspecified dementia with other behavioral disturbance
F03.92	Unspecified dementia with psychotic disturbance
F03.93	Unspecified dementia with mood disturbance
F03.94	Unspecified dementia with anxiety
F01.50	Vascular dementia without specified disturbances
F02.80	Dementia in other diseases without specified disturbances

All codes in this table reflect unspecified severity. The descriptions shorten the full ICD-10-CM wording for readability.

For complete definitions, review the CMS ICD-10-CM code files.

How to Choose the Correct Dementia ICD-10 Code

Having a clear process will ensure that the provider and billing teams do not have to correct claims unnecessarily.

Identify the Dementia Type

Find out if the provider has indicated if the patient has vascular dementia, Alzheimer’s related dementia, dementia caused by another disease or if it is unspecified.

Verify Dementia Severity

Check whether the physician has documented mild, moderate, severe or unspecified dementia. You should never assume the severity of their dementia based on cognitive test results.

Review Associated Disturbances

Check if there are any documented disturbances such as agitation, psychotic disturbance, affective disturbance, anxiety or other behavioural issues. This could affect the final code you use.

Check the Underlying Condition

If dementia is caused by an underlying disease has this been documented and does it need to be coded first using ICD-10-CM?

Top Tip for Providers: Sometimes the most specific code may not be the correct one. All information must be available to prove your coding.

Vascular Dementia ICD-10 Codes

F01 – Vascular Dementia This is used if the provider identifies vascular dementia. It could be due to cerebrovascular disease. However, do not automatically assume that the patient has vascular dementia due to a history of stroke.

Vascular Dementia Codes by Severity

Does Vascular Dementia Require an Underlying Disease Code?

If a cause is present then you will need to code the appropriate causal disease (F01). For example if the neurologist has stated that the dementia is caused by a previous cerebral infarction then the appropriate cerebrovascular sequelae code and F01 code should be considered for coding.

The link between the vascular and dementia diagnosis should be clear.

How Should Providers Code Mixed Dementia?

Some patients will have a diagnosis of vascular dementia and Alzheimer’s related dementia.

If both causes are recorded by the physician then appropriate codes and advice on coding order should be considered. Do not automatically code as unspecified dementia.

Alzheimer’s Dementia ICD-10 Codes

Alzheimer’s disease uses category G30. When the patient also has documented dementia, the coding team generally reports the appropriate G30 code and a code from F02.

Alzheimer’s Disease ICD-10 Codes

Code	Description
G30.0	Alzheimer’s disease with early onset
G30.1	Alzheimer’s disease with late onset
G30.8	Other Alzheimer’s disease
G30.9	Alzheimer’s disease, unspecified

Why Do Alzheimer’s Claims Need Two Codes?

G30 is used to identify Alzheimer’s disease. F02 is used to identify dementia due to Alzheimer’s disease.

A physician may report Moderate dementia due to unspecified Alzheimer’s disease with no disturbance.

• The G30.9 and F02.B0 would be reviewed.
• G30.9 Alzheimer’s disease, unspecified

F02.B0 Dementia in other diseases classified elsewhere, moderate degree, unspecified disturbance

Follow the code first rule. Ensure the whole documentation has been reviewed before submission.

Lewy Body, Parkinson’s, and Frontotemporal Dementia ICD-10

There are various neurological disorders that can lead to dementia and so you will need to know the specific underlying disease code.

Lewy Body Dementia

G31.83 – Dementia with Lewy Bodies. If there is mention of the correct dementia in the provider documentation then you should code with the appropriate F02 code.

Parkinson’s Disease Dementia

Parkinson’s Disease Dementia will include the correct G20 disease code. The correct F02 code will be used for the manifestation.

Dyskinesa or Fluctuations can be mentioned in the provider documentation which can affect the underlying Parkinson’s disease code.

Frontotemporal Dementia

Depending on what the physician has diagnosed this can include G31.09 or the correct underlying condition code.

It is important to look at what condition they have and what the F02 code would be.

Mild, Moderate, and Severe Dementia ICD-10 Codes

The dementia ICD-10 classification distinguishes severity because the level of impairment can change the appropriate code.

Unspecified Dementia Codes by Severity

These examples apply without documented behavioral, psychotic, mood, or anxiety disturbances.

Can Coders Determine Severity From Test Scores?

No. The FY2027 Official ICD-10-CM Coding Guidelines indicate we should use the severity stated by the provider.

While a cognitive result, a report from the carer or assessment of functional ability may impact the severity decision made by the physician, it is not for the coder to make this decision.

What if the Provider Does Not Document Severity? 

Use the relevant unspecified severity code. If there are any inconsistencies or key omissions within the documentation, you may wish to ask the provider a compliant question.

What if Dementia Progresses During Hospitalization?

If the patient had worsening dementia whilst inpatient (from mild to moderate), the coding guidelines state we should report the most severe level documented during the admission.

Do not report separate codes merely to describe each stage of the progression.

Dementia With Behavioral Disturbance ICD-10

Behavioral and psychiatric disturbances affect code selection. ICD-10-CM distinguishes agitation from other behavioral disturbances, psychosis, mood disturbance, and anxiety.

Dementia With Agitation

F03.911 applies to unspecified dementia, unspecified severity, with agitation.

For documented mild dementia with agitation, F03.A11 may apply instead.

Dementia With Psychotic Disturbance

F03.92 describes unspecified dementia, unspecified severity, with psychotic disturbance.

Dementia With Mood Disturbance

F03.93 identifies unspecified dementia, unspecified severity, with mood disturbance.

Dementia With Anxiety

F03.94 identifies unspecified dementia, unspecified severity, with anxiety.

Dementia With Other Behavioral Disturbance

F03.918 covers unspecified dementia, unspecified severity, with other behavioral disturbance, including applicable documented behavioral patterns such as social disinhibition.

What About Wandering?

If there is documentation of wandering due to dementia, check the appropriate tabular guidelines to see if another code such as Z91.83 can be used.

Do not report a nonspecific code for a disturbance if the level of severity is documented by the physician.

Dementia vs. Mild Cognitive Impairment ICD-10

Cognitive impairment does not always establish dementia. Providers should distinguish confirmed dementia from mild cognitive impairment, memory loss, and delirium.

Condition	ICD-10-CM code
Unspecified dementia	F03.90
Mild cognitive impairment of uncertain or unknown etiology	G31.84
Other amnesia or memory loss	R41.3
Delirium due to known physiological condition	F05

Can we code dementia based on memory loss?

No. As long as there is no confirmation of dementia, only the symptoms noted in the documentation can be coded. This would be memory loss.

Can someone have dementia and delirium at the same time?

Yes. If the provider has documented delirium in association with dementia then refer to the F05 code and appropriate underlying condition coding guidance.

These are different conditions so should not be used interchangeably.

What Documentation Supports Dementia ICD-10 Coding?

Providers can reduce coding uncertainty by recording the details that influence code selection.

A useful clinical note should identify:

• Confirmed dementia diagnosis and underlying cause, when known
• Documented severity level
• Associated behavioral or psychiatric disturbances
• Relevant neurological or physiological conditions
• Clinical assessment and treatment performed
• Reason for the encounter and management plan

When Should the Billing Team Request Clarification?

Use a provider query to resolve discrepancies in severity, uncertainty relating to causality or conflicting diagnoses.

In this example, if the assessment says moderate dementia and the diagnosis says mild dementia, then a query should be raised to clarify this issue. The coding team should not guess which severity to use.

Practices can strengthen this process through consistent medical coding and documentation reviews.

Dementia ICD-10 Coding Examples for Healthcare Providers

Example 1: Unspecified Dementia

Documentation: The physician confirms dementia without specifying its type, severity, or associated disturbances.

Code: F03.90

Why: The clinical note supports unspecified dementia without additional qualifying details.

Example 2: Moderate Vascular Dementia With Agitation

Documentation: A neurologist documents moderate vascular dementia with agitation and identifies the relevant underlying vascular condition.

Code: F01.B11, plus the appropriate causal condition code when applicable.

Why: The documentation supports the dementia type, severity, and disturbance. The coder must also follow the code-first instructions.

Example 3: Alzheimer’s Disease With Dementia

Documentation: The physician documents Alzheimer’s disease of unspecified onset with moderate dementia and no associated disturbances.

Codes: G30.9 followed by F02.B0.

Why: The first code identifies the underlying disease, while the second describes the dementia manifestation.

Example 4: Dementia Severity Remains Unclear

Documentation: The patient’s caregiver describes substantial assistance needs, but the physician records only unspecified dementia.

Coding action: Use the supported unspecified-severity code or seek appropriate clarification.

Why: The coder cannot independently classify the patient as having severe dementia.

Example 5: Confusion Without Confirmed Dementia

Documentation: A patient reports worsening forgetfulness, and the clinician orders further evaluation without confirming dementia.

Coding action: Report the appropriate documented symptom or confirmed condition for the outpatient encounter.

Why: A suspected diagnosis does not automatically support an outpatient dementia code.

Dementia ICD-10 Sequencing Rules

Correct code selection does not end with identifying the diagnosis. Sequencing instructions affect how the claim reports certain dementia conditions.

When Must the Underlying Disease Come First?

Category F02 requires coders to report the underlying disease before the dementia manifestation code.

Category F01 also includes a code-first instruction for an applicable causal condition.

Can Dementia Be a Secondary Diagnosis?

Yes. Dementia may be an additional diagnosis if it has affected the encounter and fits the criteria.

However, the billing team should not just put dementia as the primary diagnosis as it is a long-term diagnosis.

Do Inpatient and Outpatient Rules Differ?

Yes. Generally, uncertain diagnoses will not be coded as definite in outpatient coding.

Uncertain diagnoses can be coded at discharge in inpatient coding. Please check the appropriate guidelines for the care setting

Common Dementia ICD-10 Coding Errors

Small differences in diagnosis documentation can lead to claim edits, coding corrections, or payer requests.

Coding problem	Recommended action
Outdated dementia code	Verify code validity for the encounter date
Missing severity documentation	Use the supported code or request clarification
Incorrect behavioral disturbance	Match the code to documented findings
Missing underlying disease code	Review code-first instructions
Incomplete ICD-10 code	Confirm billable specificity
Unsupported dementia diagnosis	Verify the physician’s confirmed assessment
Incorrect diagnosis sequencing	Review the complete code combination
Diagnosis and procedure mismatch	Compare the billed service with documentation

Why Do Dementia Claims Get Rejected or Denied?

A claim may be denied at the point of submission due to an incorrect or incomplete diagnosis code. A claim that has been processed may also be denied by the payer as it cannot be supported by the evidence provided.

Different actions will be required to resolve this issue.

Review the denial, diagnosis codes, procedure codes, coverage details and evidence provided.

Structured denial management services can help you find out why this issue is occurring if it is happening on a regular basis.

Medicare Billing for Dementia-Related Services

A valid dementia diagnosis supports clinical reporting, but it does not automatically justify every cognitive assessment or care management service.

CPT 99483: Cognitive Assessment and Care Planning

Medicare uses CPT 99483 for comprehensive cognitive assessment and care planning services.

According to the CMS cognitive assessment billing guidance, practitioners must complete the required assessment elements and create a written care plan.

These elements include cognition-focused evaluation, functional assessment, medication review, safety assessment, caregiver evaluation, and appropriate care planning.

Does CPT 99483 Require a Dementia Diagnosis?

Not always. Medicare may cover the service for eligible patients with cognitive impairment, even when the clinician has not yet confirmed dementia.

The provider must meet the applicable service and documentation requirements.

Can Providers Bill CPT 99483 With an E/M Visit?

CMS identifies several office/outpatient E/M codes, including 99202–99215, that providers cannot report on the same date as 99483.

The agency provides separate instructions for combining a qualifying cognitive assessment with an Annual Wellness Visit.

Check the CMS service-specific guidance before reporting multiple services.

How Often Can Providers Report CPT 99483?

The Medicare contractor billing article A59036 states that an individual physician or qualified healthcare professional should not report CPT 99483 more than once every 180 days.

Confirm current contractor and payer requirements before billing.

Does CPT 99483 Support Telehealth?

CMS recognizes CPT 99483 as a Medicare telehealth service. Providers must still complete and document all required service elements, including information from an independent historian.

Verify current telehealth coverage, practitioner eligibility, and payer-specific billing rules.

Medicare GUIDE Model and Dementia Billing

The Guiding an Improved Dementia Experience (GUIDE) Model supports coordinated dementia care through participating organizations.

The model includes dementia care management and eligible caregiver respite services.

What Should GUIDE Participants Know?

CMS released updated GUIDE Model billing guidance in July 2026.

Under this guidance, participating organizations must submit GUIDE-specific G-codes on standalone claims and include an eligible dementia diagnosis code on applicable dementia care management claims.

Participants must also verify patient alignment, provider eligibility, and model-specific billing requirements.

Does GUIDE Apply to Every Dementia Practice?

No. The model applies to participating organizations and eligible patients. Other medical practices continue to follow their applicable Medicare and payer billing requirements.

FY2027 Dementia ICD-10 Updates: What Providers Should Check

The current FY2027 ICD-10-CM release applies from October 1, 2026, through September 30, 2027.

The CDC ICD-10-CM release page confirms that this release replaced the April 2026 code set.

Does FY2027 Change Dementia Severity Coding?

The FY2027 guidelines retain the requirement that providers document dementia severity. Coders should report unspecified severity when the record does not identify a level.

Should Practices Update Their Coding Systems?

Yes. Practices should check that their EHR, coding tools, and practice management systems use the correct code set for each date of service.

Teams should also review code descriptions, tabular notes, and any applicable payer updates instead of assuming that every previous-year coding selection remains correct.

How Tennessee Billing Helps With Dementia-Related Claims

Dementia claims may involve complex diagnosis combinations, missing documentation, and coding rules that require careful review. A reliable billing process helps providers address these issues without shifting clinical decisions away from the treating physician.

Tennessee Billing supports healthcare practices through coding reviews, claim management, and revenue cycle services.

Improve Diagnosis Coding Accuracy

Our medical coding services help practices review ICD-10-CM specificity, sequencing, supporting documentation, and claim details before submission.

Support Behavioral Health Billing

Practices that treat patients with behavioral or psychiatric conditions may also need help with evaluations, E/M coding, and payer requirements. Our psychiatry billing services support these workflows.

Resolve Repeated Claim Denials

We help practices investigate payer responses, review outstanding claims, and identify recurring coding or documentation issues through denial management.

Review Coverage Before Services

Cognitive assessments and related care may involve specific coverage or benefit requirements. Our insurance eligibility verification services help practices review available insurance details and applicable requirements.

Support the Complete Revenue Cycle

Our medical billing services in Tennessee support practices across Nashville, Memphis, Knoxville, Chattanooga, and surrounding communities.

We focus on accurate claim preparation, timely follow-up, and practical improvements that reduce avoidable billing work.

Dementia ICD-10 Pre-Submission Checklist

Before submitting a dementia-related claim, complete these checks:

• Confirm the provider’s dementia diagnosis.
• Identify the dementia type and underlying disease.
• Verify documented severity.
• Review behavioral and psychiatric disturbances.
• Check current ICD-10-CM code specificity.
• Apply code-first and sequencing instructions.
• Match diagnosis codes to documented services.
• Review payer coverage and authorization requirements.
• Confirm final claim details before submission.

A short review before submission can help billing teams catch discrepancies while the clinical record remains readily available.

Frequently Asked Questions

What is the ICD-10 code for dementia?

F03.90 is used for unspecified dementia not otherwise specified (NOS). There are other codes available if the healthcare provider has documented a specific type, severity or qualifying dementia.

What is the ICD-10 code for vascular dementia?

F01.50 indicates vascular dementia not otherwise specified. There are more specific codes under F01 if a specific severity or qualifying dementia can be identified from the documentation.

What is the ICD-10 code for dementia with behavioral disturbance?

This will depend on the type, severity and behaviour of the dementia. For example: F03.911 is used for unspecified dementia not otherwise specified with agitated behaviour. F03.918 indicates other behavioural disturbance dementia.

What is the difference between F01, F02, and F03 dementia codes?

F01 indicates vascular dementia. F02 indicates dementia caused by diseases classified elsewhere. F03 indicates unspecified dementia.

Can providers use F03.90 for Alzheimer’s dementia?

If it is confirmed that the patient has dementia caused by Alzheimer’s disease, the correct G30 and F02 combination should be reviewed by the coders.

Does dementia severity affect ICD-10 coding?

Yes. ICD-10-CM recognises mild, moderate, severe and unspecified dementia. This must be documented by the healthcare provider.

Can medical coders determine dementia severity from assessment scores?

No. The severity must be determined by the healthcare provider treating the patient.

Can dementia and delirium appear on the same claim?

Yes. If the documentation supports this diagnosis and the ICD-10-CM instructions allow this to happen. Look at the underlying condition and ordering.

Final Thoughts

Accurate dementia ICD-10 coding starts with a complete diagnosis and ends with a careful claim review. Providers must document the dementia type, severity, associated disturbances, and underlying conditions so billing teams can select the appropriate codes.

The most effective approach combines current ICD-10-CM guidance, clear clinical documentation, correct sequencing, and timely correction of claim discrepancies.

Give Dementia Claims a Stronger Coding Review

Missing severity details, incorrect diagnosis combinations, and repeated claim corrections can create unnecessary work for your practice.

Get help reviewing your coding and billing process, identifying recurring problems, and improving claim accuracy.

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