Memory Loss ICD-10 Codes - What Your Documentation Is Getting Wrong in 2026

Memory loss is one of those diagnoses that looks deceptively simple on the surface. A patient forgets names. They struggle to recall recent events. The clinician notes it. And then the coder stares at the chart and realizes: which code actually applies here?

The 2026 edition of ICD-10-CM became effective on October 1, 2025 and with it came updated guidance on how memory-related diagnoses should be documented, sequenced, and reported for reimbursement. 

This guide covers every major memory loss ICD 10 code in the 2026 edition, organized by clinical scenario, with documentation pointers and billing considerations throughout.

What Does Memory Loss Mean in ICD-10

Before selecting a code, coders must understand what ICD-10-CM actually captures under “memory loss.” The system does not treat it as a single, monolithic diagnosis. It distinguishes between:

• Memory loss as an isolated, unspecified symptom.
• Memory loss tied to a known physiological cause, such as dementia or brain injury.
• Age-related cognitive decline without a pathological diagnosis.
• Amnestic disorders triggered by substances such as alcohol.
• Cognitive deficits arising as sequelae of cerebrovascular events.

Each of these pathways leads to a different code family, and selecting the wrong one puts your claim at risk.

The Primary Code for Memory Loss Unspecified

When clinical documentation supports memory loss as a presenting symptom without identifying a specific underlying cause, the go-to code is:

R41.3 — Other Amnesia

R41.3 carries the approximate synonym “Memory loss NOS” and covers systematic and extensive loss of memory caused by organic or psychological factors. The loss may be temporary or permanent and may involve old or recent memories.

This is a billable and specific code. It is valid for reimbursement and is grouped within MS-DRG v43.0: 884, which covers organic disturbances and intellectual disability.

When to Use R41.3

Use R41.3 when:

• The provider documents memory loss or amnesia without specifying etiology.
• The workup is still ongoing and no confirmed underlying diagnosis exists.
• The memory complaint is the primary reason for the encounter.

What R41.3 Excludes

Coders must pay close attention to the exclusion notes under R41.3. It has both Type 1 and Type 2 exclusions:

Type 1 Excludes (never code together with R41.3):

• Amnestic disorder due to known physiologic condition (F04).
• Retrograde amnesia (R41.2).
• Transient global amnesia (G45.4).
• Mild memory disturbance due to known physiological condition (F06.8).

Type 2 Excludes (code separately when applicable):

• Alcohol-induced or unspecified Korsakov’s syndrome (F10.26, F10.96) and Korsakov’s syndrome induced by other psychoactive substances (F13.26, F13.96, F19.16, F19.26, F19.96)

Understanding these exclusions prevents upcoding errors and audit exposure. If the documentation clearly states a cause, R41.3 is not the right home for that claim.

R41.3 ICD 10 in Context with In The Full R41 Family

R41.3 sits within the broader R41 category, which covers other symptoms and signs involving cognitive functions and awareness. Coders working with memory complaints should also be familiar with adjacent codes:

Each has its own clinical criteria and documentation requirements. Assigning R41.3 when the documentation actually supports R41.2 (retrograde amnesia) or R41.89 is a specificity failure that could trigger payer scrutiny.

For practices managing complex neurology or geriatric billing, working with a dedicated coding partner helps ensure every encounter is mapped to its most defensible code. IRCM’s medical coding services are built for exactly this kind of clinical complexity.

ICD 10 Code for Memory Loss Due to Age

Not all memory complaints point to a pathological process. Some represent a normal, age-related pattern of cognitive slowing that does not meet criteria for dementia or mild cognitive impairment.

R41.81 — Age-Related Cognitive Decline

R41.81 is a billable, specific ICD-10-CM code applicable to adult patients aged 15 to 124 years, and the 2026 edition became effective on October 1, 2025. Its approximate synonym is “Senility.” 

This code is appropriate when:

• The provider documents normal forgetfulness consistent with aging.
• Cognitive testing does not reveal pathological impairment.
• There is no diagnosis of dementia, MCI, or neurological disorder.

R41.81 should not be used in place of a more specific diagnosis when one is established. It is a symptom-level code, not a diagnostic one.

ICD 10 Code for Mild Cognitive Impairment with Memory Loss

When memory loss is accompanied by measurable cognitive decline, but falls short of dementia, the appropriate code is:

G31.84 — Mild Cognitive Impairment of Uncertain or Unknown Etiology

The 2026 edition of ICD-10-CM G31.84 became effective on October 1, 2025. It covers mild cognitive disorder NOS and mild neurocognitive disorder of uncertain or unknown etiology. 

This code is relevant in scenarios where:

• Neuropsychological testing confirms cognitive decline beyond age-expected norms.
• The provider has not yet attributed the decline to a specific disease process.
• The patient does not meet clinical criteria for dementia.

G31.84 excludes age-related cognitive decline (R41.81), altered mental status (R41.82), and cognitive impairment due to intracranial or head injury (S06.-).

Important: G31.84 carries a “Use Additional Code” instruction. When alcohol abuse or dependence is present, coders should add the appropriate F10 code alongside G31.84.

For practices in neurology and geriatrics dealing with MCI billing, documentation must include cognitive test scores, functional assessment results, and the provider’s clinical rationale for the diagnosis. Missing any of these elements is among the top drivers of claim denial in this category. IRCM’s neurology billing specialists understand the level of documentation that payers require for these encounters.

ICD 10 Code for Memory Loss Due to Dementia

When memory loss is a manifestation of dementia, the coding approach becomes more layered. ICD-10-CM uses an etiology/manifestation convention, meaning you are required to code the underlying disease first, followed by the dementia manifestation code.

Unspecified Dementia

F03.90 — Unspecified Dementia, Unspecified Severity, Without Behavioral Disturbance

F03.90 covers a condition in which a person loses the ability to think, remember, learn, make decisions, and solve problems. Memory loss is a common symptom of dementia, though memory loss by itself does not mean a patient has dementia.

F03 codes are stratified by severity (unspecified, mild, moderate, severe) and by the presence or absence of behavioral disturbance, psychotic disturbance, mood disturbance, or anxiety.

Alzheimer’s Disease with Dementia

For patients where Alzheimer’s disease drives the memory impairment, ICD-10-CM requires two codes: one from category G30 (Alzheimer’s disease) and one from category F02 (Dementia in other diseases classified elsewhere). The etiology code G30 is sequenced first, followed by the manifestation code F02

Common Alzheimer’s code options:

Each must be paired with an F02 manifestation code that reflects severity and any behavioral disturbance present.

A common documentation failure in Alzheimer’s billing is the absence of severity staging. Without the provider explicitly documenting mild, moderate, or severe, the claim defaults to unspecified severity, which payers increasingly flag during audit.

ICD 10 Code for Memory Loss Due to Alcohol

Alcohol-related memory loss represents one of the more nuanced coding scenarios in this clinical area. There are two distinct pathways depending on the level of alcohol use documented.

For Alcohol Dependence with Persisting Amnestic Disorder

F10.26 — Alcohol Dependence with Alcohol-Induced Persisting Amnestic Disorder

F10.26 is a billable, specific ICD-10-CM code effective for the 2026 edition. Its approximate synonyms include alcohol use disorder, moderate, with alcohol-induced major neurocognitive disorder, amnestic-confabulatory type.

For Unspecified Alcohol Use with Persisting Amnestic Disorder

F10.96 — Alcohol Use, Unspecified with Alcohol-Induced Persisting Amnestic Disorder

F10.96 carries the approximate synonym “Alcohol induced amnestic disorder” in the 2026 ICD-10-CM edition.

Both F10.26 and F10.96 are commonly associated with Korsakov’s syndrome, the thiamine-deficiency-related memory disorder seen in chronic heavy drinkers. When alcohol-induced dementia (rather than isolated amnesia) is the documented diagnosis, use F10.27 or F10.97 respectively.

Coders must never default to R41.3 when alcohol use is the documented cause. The Type 2 Excludes notation under R41.3 makes clear that these F10 codes are the appropriate classification.

ICD 10 Code for Mild Memory Loss

When the provider documents mild or early-stage memory difficulties without a full cognitive impairment diagnosis, coders have a few options depending on context:

• R41.3 when it is symptom-level, unspecified memory loss.
• G31.84 when mild cognitive impairment has been clinically established.
• F06.8 when mild memory disturbance is linked to a known physiological condition.

The word “mild” in documentation does not automatically map to G31.84. It must be supported by clinical testing and provider-level diagnostic language. Coding based on symptom description alone without a confirmed diagnosis is a compliance risk that exposes practices to recovery audit scrutiny.

For practices unsure about where to draw that line, IRCM’s denial management services can help identify where imprecise coding is generating preventable denials.

ICD 10 Code for Memory Loss Due to Head Injury

Traumatic brain injury and cranial trauma are common antecedents to persistent memory difficulties. ICD-10-CM handles this through the S06 category for intracranial injury.

S06 — Intracranial Injury (with appropriate 7th character)

When coding memory loss following traumatic brain injury, providers should pair the S06 intracranial injury code with a symptom code such as R41.3 for memory loss NOS. The 7th character designates whether the encounter is initial (A), subsequent (D), or sequela (S). NCBI

For late effects of TBI, the symptom code comes first, followed by the injury code with the 7th character “S” for sequela. This pairing structure is essential to accurately link the memory complaint to its traumatic origin.

When cognitive impairment following head injury does not meet the threshold of dementia, the appropriate additional code is F06.7 (mild neurocognitive disorder due to known physiological condition), which must be used alongside the S06 sequela code when applicable.

ICD 10 Code for Memory Loss Due to Stroke / CVA

Stroke is one of the most well-documented causes of post-event cognitive decline and memory impairment. ICD-10-CM addresses these sequelae through the I69 category.

I69.311 — Memory Deficit Following Cerebral Infarction

The 2026 edition of ICD-10-CM I69.311 became effective on October 1, 2025. It captures memory deficit as a sequela of cerebral infarction.

The I69 category has parallel code sets for each type of cerebrovascular event:

Sequencing note: With I69 codes, the sequela code itself (I69.311 or its equivalent) is used at the time of the late-effect encounter. There is no need to separately add R41.3 when an I69 specificity code already captures the memory deficit.

Neurology and stroke rehabilitation practices generate a significant volume of these encounters. Precise sequela coding directly affects MS-DRG assignment and reimbursement levels.

Cognitive Impairment ICD 10 at a Glance

Below is a consolidated reference table of the most commonly used cognitive impairment ICD-10 codes in 2026:

Documentation That Protects Your Claims

Selecting the right code is only half the battle. The documentation supporting that selection is what survives an audit. Here is what payers expect to see in the clinical record when memory loss is the working diagnosis:

For R41.3 (unspecified memory loss):

• Patient-reported symptoms with onset, duration, and functional impact.
• Any cognitive screening results (MMSE, MoCA, etc.).
• A clear statement that no confirmed etiology has been established yet.

For G31.84 (mild cognitive impairment):

• Neuropsychological or cognitive test scores with age-adjusted norms.
• Provider’s clinical interpretation of test results.
• Functional status and daily living impact.
• Exclusion of dementia documented explicitly.

For F10.26 / F10.96 (alcohol-related amnesia):

• Documented history of alcohol use disorder with type (abuse vs. dependence).
• Clinical findings consistent with amnestic syndrome.
• Exclusion of other organic causes where relevant.

For I69.311 and related stroke sequelae:

• Date and type of original cerebrovascular event.
• Neurological findings linking memory deficit to the prior event.
• Relevant imaging or clinical notes confirming the sequela relationship.

Gaps in any of these documentation areas create claim vulnerabilities. IRCM’s medical coding services include documentation feedback that helps clinicians provide the clinical detail coders need before the claim ever leaves the practice.

The Billing and Revenue Impact of Getting This Right

Memory and cognitive disorder visits are among the higher-acuity, higher-value encounters in outpatient medicine. When codes are assigned with specificity, they support appropriate DRG grouping, justify the level of evaluation and management service billed, and reduce the likelihood of additional development requests from Medicare and commercial payers.

When they are wrong, the downstream impact is real. Undercoding reduces reimbursement. Overcoding triggers audits. And unspecified codes, used when specific ones are supported by documentation, leave both compliance risk and revenue on the table simultaneously.

Understanding how to apply the memory loss ICD 10 code framework correctly is not a minor administrative matter. For neurologists, geriatric medicine specialists, and primary care providers seeing aging populations, it directly shapes the financial health of the practice.

If your team is navigating the complexity of cognitive impairment coding or facing denials on memory-related claims, IRCM’s Coders are equipped to help you build a cleaner, more defensible revenue cycle from the diagnosis level forward.