G30.9 ICD-10-CM Code: Alzheimer's disease, unspecified
G30.9 maps to CMS-HCC V28 127 (RAF 0.341). Documentation must support MEAT. MEAT criteria · RAF calculator · HCC Buddy coding tools
HCC Buddy Code Card
Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.
FY 2026 Apr update / Diseases of the nervous system (G00-G99) / Other degenerative diseases of the nervous system (G30-G32)
G30.9
Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidanceAlzheimer's disease, unspecified
Alzheimer's disease without specification of the stage or type; the most common form of dementia causing progressive memory loss and cognitive decline.
Buddy Insight
Alzheimer's disease, unspecified, captures confirmed Alzheimer's diagnoses where the onset type or variant has not been documented.
CMS-HCC V28
MappedHCC 127
RAF 0.341
CMS-HCC V24
MappedHCC 52
RAF 0.346
ACA/HHS
N/A—
Not mapped
ESRD/PACE
MappedHCC 52
RAF 0.042
RXHCC
MappedHCC 111
Not separately weighted
Code Book Path
Inclusion Terms
OfficialICD-10-CM does not list inclusion terms for G30.9 in this effective period.
Excludes 2
OfficialICD-10-CM does not list Excludes 2 notes for G30.9 in this effective period.
Related Child Codes
Includes
Official- Alzheimer's dementia senile and presenile forms
Excludes 1
Official- senile degeneration of brain NEC (G31.1)
- senile dementia NOS (F03.-)
- senility NOS (R41.81)
Code First
OfficialICD-10-CM does not list Code First sequencing instructions for G30.9 in this effective period.
Use Additional
Official- code, if applicable, to identify:
- delirium, if applicable (F05)
- dementia with anxiety (F02.84, F02.A4, F02.B4, F02.C4)
- dementia with behavioral disturbance (F02.81-, F02.A1-, F02.B1-, F02.C1-)
- dementia with mood disturbance (F02.83, F02.A3, F02.B3, F02.C3)
Code Also
OfficialICD-10-CM does not list Code Also instructions for G30.9 in this effective period.
Buddy Documentation Tip
MEAT Support
Audit Caution
Common Mistakes
Current with CMS: FY2026 ICD-10-CM Apr 1 update (effective Apr 1 – Sep 30, 2026) · CMS-HCC V28, 100% phased in for payment year 2026. FY2027 code set already staged for October 1, 2026. How HCC Buddy stays current →
Is G30.9 an HCC code?
Yes. G30.9 (Alzheimer's disease, unspecified) maps to Dementia, Mild or Unspecified under the CMS-HCC V28 risk adjustment model (and Dementia Without Complication under V24), with a community non-dual aged RAF of 0.341. It is billable for payment year 2026.
Coder answer: G30.9 is billable and maps to V28 HCC 127, Dementia, Mild or Unspecified. Open it in the Code Book for the tabular path, RAF, and MEAT checklist.
- Code
- G30.9
- Description
- Alzheimer's disease, unspecified
- HCC (V28)
- HCC 127 — Dementia, Mild or Unspecified
- RAF
- 0.341
- Billable
- Yes
- Payment year
- 2026
HCC Category Mapping
Each model's RAF is its CMS base weight for that model's standard population, so weights are not directly comparable across models: CMS-HCC V28 and V24 use Community, Non-Dual, Aged; ESRD uses the dialysis continuing-enrollee model; RxHCC is the Part D continuing-enrollee, non-low-income, aged weight (a larger scale than CMS-HCC). ACA/HHS has no single weight — it varies by metal level. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
Work G30.9 in the Code Book — tabular path, V28 RAF, and MEAT checklist →
MEAT Criteria for G30.9
For G30.9 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed G30.9 during that encounter, not just copy-forwarded from a problem list.
Coder workflow notes
Get the V28 RAF + MEAT cheat sheet
One printable page: confirm a code's V28 HCC status, its RAF weight, and the MEAT your note needs to make it stick. Free, no card.
Free PDF. No card. Unsubscribe anytime.
What This Code Means
G30.9 is the ICD-10-CM diagnosis code for alzheimer's disease, unspecified. Alzheimer's disease without specification of the stage or type; the most common form of dementia causing progressive memory loss and cognitive decline. G30.9 sits in the ICD-10-CM chapter for diseases of the nervous system (g00-g99), within the section covering other degenerative diseases of the nervous system (g30-g32).
Under the CMS-HCC V28 risk adjustment model, G30.9 maps to Dementia, Mild or Unspecified (HCC 127) with a community, non-dual, aged base RAF weight of 0.341. Under the older CMS-HCC V24 model, G30.9 maps to Dementia Without Complication (HCC 52) with a community, non-dual, aged base RAF weight of 0.346. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
Alzheimer's disease, unspecified, provider documents Alzheimer's without specifying early vs late onset. Pair with F02.8x per 'code first' convention. Because G30.9 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for G30.9 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Alzheimer's disease, unspecified, provider documents Alzheimer's without specifying early vs late onset. Pair with F02.8x per 'code first' convention.
- •Do not default to G30.9 when the chart supports early (G30.0) or late (G30.1) onset. Onset specificity is a minor chart-quality improvement.
- •G30.9 plus F02.8x drives V28 HCC 127 at RAF 0.341.
Clinical Significance
Alzheimer's disease, unspecified, captures confirmed Alzheimer's diagnoses where the onset type or variant has not been documented. While it carries the same HCC value as more specific Alzheimer's codes, it represents a documentation improvement opportunity. Accurate capture still ensures proper risk adjustment for these patients with progressive cognitive decline requiring substantial care resources.
Documentation Requirements
- ✓Provider documentation confirming Alzheimer's disease diagnosis
- ✓Cognitive assessment demonstrating decline (MMSE, MoCA, or equivalent)
- ✓Evidence of progressive memory loss and functional impairment
- ✓Current medication management and care plan
- ✓Assessment for associated behavioral or psychological symptoms
Commonly Confused Codes
- •G30.0: Alzheimer's disease with early onset; query provider if onset age is available
- •G30.1: Alzheimer's disease with late onset; query provider if onset age is documented
- •F03.90: Unspecified dementia; too vague if Alzheimer's has been specifically diagnosed
- •G31.84: Mild cognitive impairment; a milder condition that may precede Alzheimer's but is not the same
- •R41.81: Age-related cognitive decline; normal aging, not Alzheimer's disease