G35 ICD-10-CM Code: Multiple sclerosis
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) / Demyelinating diseases of the central nervous system (G35-G37)
G35
Header CodeICD-10-CMOfficial ICD-10-CMCodebook guidanceMultiple sclerosis
Multiple sclerosis
CMS-HCC V28
MappedHCC 198
RAF 0.0
CMS-HCC V24
MappedHCC 77
RAF 0.476
ACA/HHS
00
RAF 0
ESRD/PACE
MappedHCC 77
RAF 0.0
RXHCC
MappedHCC 159
RAF 0.0
Code Trumping
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Code Book Path
Inclusion Terms
OfficialICD-10-CM does not list inclusion terms for G35 in this effective period.
Excludes 2
OfficialICD-10-CM does not list Excludes 2 notes for G35 in this effective period.
Related Child Codes
Includes
OfficialICD-10-CM does not list Includes notes for G35 in this effective period.
Excludes 1
OfficialICD-10-CM does not list Excludes 1 notes for G35 in this effective period.
Code First
OfficialICD-10-CM does not list Code First sequencing instructions for G35 in this effective period.
Use Additional
OfficialICD-10-CM does not list Use Additional Code instructions for G35 in this effective period.
Code Also
OfficialICD-10-CM does not list Code Also instructions for G35 in this effective period.
Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.
Is G35 an HCC code?
Yes. G35 maps to Multiple Sclerosis under the CMS-HCC V28 risk adjustment model (and Multiple Sclerosis under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. 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.
MEAT Criteria for G35
For G35to 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 G35 during that encounter, not just copy-forwarded from a problem list.
What This Code Means
G35 is the ICD-10-CM diagnosis code for multiple sclerosis. G35 sits in the ICD-10-CM chapter for diseases of the nervous system (g00-g99), within the section covering demyelinating diseases of the central nervous system (g35-g37).
Under the CMS-HCC V28 risk adjustment model, G35 maps to Multiple Sclerosis (HCC 198) with a community, non-dual, aged base RAF weight of 0.000. Under the older V24 model, G35 mapped to the same category but with a base RAF weight of 0.476, V28 recalibrated weights across the entire model. 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.
Header codes like G35 cannot be reported on claims directly, they organize child codes that share clinical context but the actual diagnosis must be coded to the highest level of specificity supported by the documentation. Coders should look at G35's child codes and select the one that matches the patient's documented presentation, since payers reject header codes submitted as the primary diagnosis. For risk adjustment workflows, header codes never contribute to a Medicare Advantage member's RAF score on their own; only billable child codes that happen to map to a payment HCC affect risk-adjusted plan payments.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for G35 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.