What is ICD-10 code G43.901?

G43.901 is the ICD-10-CM diagnosis code for Migraine, unspecified, not intractable, with status migrainosus. A migraine headache of unspecified type that can be managed with treatment and has prolonged symptoms lasting 72 hours or more. G43.901 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. G43.901 is part of the FY2026 ICD-10-CM code set published by the CMS National Center for Health Statistics and used on Medicare, Medicaid, and commercial claims in the United States.

Yes. G43.901 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. G43.901 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

Which HCC does G43.901 map to under V28?

G43.901 does not map to a CMS-HCC V28 payment category. Check the current CMS-HCC V28 model file for payment year 2026 rather than an older V24 tip sheet.

What does G43.901 pay in RAF?

G43.901 has no separately stated V28 community RAF weight. If it is not a V28 payment HCC, it adds nothing to a community RAF score.

What is the V28 vs V24 difference for G43.901?

G43.901 does not map to a payment HCC under either the CMS-HCC V28 risk adjustment model or the older V24 model. V28 reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition. Because neither community model rewards G43.901 with a risk adjustment factor, it contributes zero to a Medicare Advantage beneficiary's V28/V24 community RAF score in either version. It does, however, map under the Part D RxHCC model (Migraine), which affects the ESRD and/or Part D (RxHCC) risk scores. Coders should check whether provider documentation supports a more specific child code that does map to a community payment HCC.

What documentation supports G43.901?

Use this code only when the specific migraine type cannot be determined from documentation Status migrainosus must be documented; this indicates a migraine emergency requiring hospitalization G43.901 is not a CMS-HCC payment code, so MEAT is not the payment hook. Documentation still has to support the diagnosis if you report it.

2026 ICD-10-CM G43.901: Migraine, unspecified, not

G43.901 is not a CMS-HCC payment code. MEAT criteria · RAF calculator · free HCC coding tools

ICD-10-CM Code View

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Code lookupG43.901Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Diseases of the nervous system (G00-G99) / Episodic and paroxysmal disorders (G40-G47)

G43.901

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Migraine, unspecified, not intractable, with status migrainosus

A migraine headache of unspecified type that can be managed with treatment and has prolonged symptoms lasting 72 hours or more.

Buddy Insight

Unspecified migraine codes are used when the provider documents migraine but does not specify the subtype (with/without aura, hemiplegic, chronic, etc.

CMS-HCC V28

N/A

—

Not risk-adjusted for this model/period.

Not mapped

CMS-HCC V24

N/A

—

Not risk-adjusted for this model/period.

Not mapped

ACA/HHS

N/A

—

Not risk-adjusted for this model/period.

Not mapped

ESRD/PACE

N/A

—

Not risk-adjusted for this model/period.

Not mapped

RXHCC

Mapped

HCC 166

Migraine

RAF 0.100

Code Book Path

Official

G43.9Migraine, unspecified

G43.90Migraine, unspecified, not intractable

G43.901Migraine, unspecified, not intractable, with status migrainosus

Inclusion Terms

Official

Status migrainosus NOS

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for G43.901 in this effective period.

Related Child Codes

Official

G43.909Migraine, unspecified, not intractable, without status migrainosus

Includes

Official

ICD-10-CM does not list Includes notes for G43.901 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for G43.901 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for G43.901 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for G43.901 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for G43.901 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Provider documentation of migraine diagnosis (even without subtype specification)

Treatment response documented, or default to not intractable if not specified

Status migrainosus with duration >72 hours

Query opportunity: check for aura symptoms, frequency pattern, or specific variant that would support a more specific code

MEAT Support

HCC Buddy guidance

Provider documentation of migraine diagnosis (even without subtype specification)

Treatment response documented, or default to not intractable if not specified

Status migrainosus with duration >72 hours

Query opportunity: check for aura symptoms, frequency pattern, or specific variant that would support a more specific code

Audit Caution

HCC Buddy guidance

Accepting unspecified migraine when the medical record contains enough detail to code a specific subtype

Not querying the provider when aura status, frequency, or variant type is documented elsewhere in the record

Defaulting to unspecified for all migraine encounters rather than reviewing for specificity

Using unspecified codes for conditions that clearly match hemiplegic, chronic, or other specific migraine subtypes

Common Mistakes

HCC Buddy guidance

G43.001-G43.019 (Migraine without aura) — use when provider documents absence of aura; more specific than unspecified

G43.101-G43.119 (Migraine with aura) — use when visual/sensory/speech aura is documented

G43.701-G43.719 (Chronic migraine without aura) — use when frequency >=15 days/month is documented

R51.9 (Headache, unspecified) — even more nonspecific; use migraine codes when migraine is diagnosed

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 G43.901 an HCC code?

G43.901 is not in the CMS-HCC V28 or V24 community payment model, but it does map to Migraine under the Part D RxHCC model.

Code: G43.901
Description: Migraine, unspecified, not intractable, with status migrainosus
HCC (V28): No CMS-HCC V28 mapping
RAF: —
Billable: Yes
Payment year: 2026

HCC Category Mapping

RxHCCHCC 166, Migraine

0.100

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 G43.901 in the Code Book — tabular path, V28 RAF, and MEAT checklist →

MEAT Criteria for G43.901

For G43.901 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 G43.901 during that encounter, not just copy-forwarded from a problem list.

Coder workflow notes

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What This Code Means

G43.901 is the ICD-10-CM diagnosis code for migraine, unspecified, not intractable, with status migrainosus. A migraine headache of unspecified type that can be managed with treatment and has prolonged symptoms lasting 72 hours or more. G43.901 sits in the ICD-10-CM chapter for diseases of the nervous system (g00-g99), within the section covering episodic and paroxysmal disorders (g40-g47).

G43.901 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

This code does not map to a CMS-HCC V28 payment category. Capture depends on documentation that supports the diagnosis; verify the HCC assignment against the current CMS mapping for the applicable payment year. Coders reviewing G43.901 should check whether additional documentation would support a more specific child code in the same hierarchy that does map to a payment HCC, capturing the correct specificity is the highest-impact RAF improvement available within accurate coding.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for G43.901 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•Use this code only when the specific migraine type cannot be determined from documentation
•Status migrainosus must be documented; this indicates a migraine emergency requiring hospitalization

Clinical Significance

Unspecified migraine codes are used when the provider documents migraine but does not specify the subtype (with/without aura, hemiplegic, chronic, etc.). While these codes are valid, they represent a missed opportunity for specificity and should prompt coders to query the provider for additional detail. Unspecified codes still map to RxHCC 166 and capture the pharmacy risk associated with migraine treatment.

Documentation Requirements

✓Provider documentation of migraine diagnosis (even without subtype specification)
✓Treatment response documented, or default to not intractable if not specified
✓Status migrainosus with duration >72 hours
✓Query opportunity: check for aura symptoms, frequency pattern, or specific variant that would support a more specific code
✓Migraine features present (headache with at least some typical migraine characteristics)
✓Current treatment plan

Commonly Confused Codes

•G43.001-G43.019 (Migraine without aura): use when provider documents absence of aura; more specific than unspecified
•G43.101-G43.119 (Migraine with aura): use when visual/sensory/speech aura is documented
•G43.701-G43.719 (Chronic migraine without aura): use when frequency >=15 days/month is documented
•R51.9 (Headache, unspecified): even more nonspecific; use migraine codes when migraine is diagnosed
•G44.1 (Vascular headache, NEC): different classification; migraine should be coded as migraine

Child Codes

G43.901Migraine, unspecified, not intractable, with status migrainosus

G43.909Migraine, unspecified, not intractable, without status migrainosus

Code Hierarchy

└G43Migraine └G43.9Migraine, unspecified └G43.90Migraine, unspecified, not intractable └G43.901Migraine, unspecified, not intractable, with status migrainosus

└G43.901Migraine, unspecified, not intractable, with status migrainosus

G43.901 ICD-10-CM Code: Migraine, unspecified, not intractable, with status migrainosus

HCC Buddy Code Card

G43.901

Is G43.901 an HCC code?

HCC Category Mapping

MEAT Criteria for G43.901

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What This Code Means

Coding Tips

Clinical Significance

Documentation Requirements

Commonly Confused Codes

Child Codes

Code Hierarchy

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