What is ICD-10 code M06.0A?

M06.0A is the ICD-10-CM diagnosis code for Rheumatoid arthritis without rheumatoid factor, other specified site. Rheumatoid arthritis without the typical blood marker affecting a joint site not covered by the other specific codes. M06.0A is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. M06.0A 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. M06.0A 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. M06.0A 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 M06.0A map to under V28?

M06.0A maps to CMS-HCC V28 93 (Rheumatoid Arthritis and Other Specified Inflammatory Rheumatic Disorders). The category number and label come from the CMS-HCC V28 model file for payment year 2026.

What does M06.0A pay in RAF?

M06.0A carries a community, non-dual, aged (CNA) RAF weight of 0.617 under CMS-HCC V28 for payment year 2026. The weight comes from the CMS V28 relative-factor file, not a hand-typed table.

What is the V28 vs V24 difference for M06.0A?

CMS phased in the V28 risk adjustment model over payment years 2024 (33%), 2025 (67%), and 2026 (100%), replacing V24. V28 consolidates HCC categories, removes some lower-acuity conditions, and recalibrates RAF weights across the entire model. For M06.0A, V28 maps to Rheumatoid Arthritis and Other Specified Inflammatory Rheumatic Disorders at RAF 0.617 while V24 mapped to Rheumatoid Arthritis and Inflammatory Connective Tissue Disease at RAF 0.421. Both models can still appear in legacy data and in payer-specific lookback periods.

What documentation supports M06.0A?

Clearly document the specific anatomical site affected in the medical record Use this code only when the affected site does not fit into the standard categories (shoulder, elbow, wrist, hip, knee, ankle, foot, vertebrae, or multiple sites) Because M06.0A maps to a payment HCC, the documentation must also satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's risk adjustment score. See the MEAT criteria checklist at /meat-criteria for what Monitor, Evaluate, Assess, or Treat looks like in a note. MEAT is generic documentation evidence, not a payer-specific rule.

2026 ICD-10-CM M06.0A: Rheumatoid arthritis

M06.0A maps to CMS-HCC V28 93 (RAF 0.617). Documentation must support MEAT. MEAT criteria · RAF calculator · free HCC coding tools

ICD-10-CM Code View

HCC Buddy Code Card

Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.

Code lookupM06.0AEffective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Diseases of the musculoskeletal system and connective tissue (M00-M99) / Inflammatory polyarthropathies (M05-M14)

M06.0A

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

Rheumatoid arthritis without rheumatoid factor, other specified site

Rheumatoid arthritis without the typical blood marker affecting a joint site not covered by the other specific codes.

Buddy Insight

Seronegative rheumatoid arthritis affecting other specified sites indicates RA involvement in joints not covered by other specific anatomical codes.

CMS-HCC V28

Mapped

HCC 93

Rheumatoid Arthritis and Othe...

RAF 0.617

CMS-HCC V24

Mapped

HCC 40

Rheumatoid Arthritis and Infl...

RAF 0.421

ACA/HHS

Mapped

HCC 56

HHS-HCC 56

Varies by metal level

ESRD/PACE

Mapped

HCC 40

Rheumatoid Arthritis and Infl...

RAF 0.058

RXHCC

Mapped

HCC 83

Rheumatoid Arthritis and Infl...

RAF 0.222

Code Book Path

Official

M06Other rheumatoid arthritis

M06.0Rheumatoid arthritis without rheumatoid factor

M06.0ARheumatoid arthritis without rheumatoid factor, other specified site

Inclusion Terms

Official

ICD-10-CM does not list inclusion terms for M06.0A in this effective period.

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for M06.0A in this effective period.

Related Child Codes

Official

M06.00Rheumatoid arthritis without rheumatoid factor, unspecified site

M06.01Rheumatoid arthritis without rheumatoid factor, shoulder

M06.02Rheumatoid arthritis without rheumatoid factor, elbow

M06.03Rheumatoid arthritis without rheumatoid factor, wrist

M06.04Rheumatoid arthritis without rheumatoid factor, hand

Includes

Official

ICD-10-CM does not list Includes notes for M06.0A in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for M06.0A in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for M06.0A in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for M06.0A in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for M06.0A in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Confirmed rheumatoid arthritis diagnosis by qualified physician

Laboratory evidence of negative rheumatoid factor status

Specific documentation of affected joint site not elsewhere classified

Clinical evidence of inflammatory arthritis in specified location

MEAT Support

HCC Buddy guidance

Confirmed rheumatoid arthritis diagnosis by qualified physician

Laboratory evidence of negative rheumatoid factor status

Specific documentation of affected joint site not elsewhere classified

Clinical evidence of inflammatory arthritis in specified location

Audit Caution

HCC Buddy guidance

Using this code when a more specific anatomical code exists

Failing to clearly document the specific site involved

Not verifying seronegative status before code assignment

Confusing with arthritis of temporomandibular joint or other specific sites

Common Mistakes

HCC Buddy guidance

M05.8A — Rheumatoid arthritis WITH rheumatoid factor, other specified site

M06.09 — RA without RF, multiple sites (when multiple joints involved)

M13.8A — Other specified arthritis, other specified site

M25.50 — Pain in unspecified joint

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 M06.0A an HCC code?

Yes. M06.0A (Rheumatoid arthritis without rheumatoid factor, other specified site) maps to Rheumatoid Arthritis and Other Specified Inflammatory Rheumatic Disorders under the CMS-HCC V28 risk adjustment model (and Rheumatoid Arthritis and Inflammatory Connective Tissue Disease under V24), with a community non-dual aged RAF of 0.617. It is billable for payment year 2026.

Coder answer: M06.0A is billable and maps to V28 HCC 93, Rheumatoid Arthritis and Other Specified Inflammatory Rheumatic Disorders. Open it in the Code Book for the tabular path, RAF, and MEAT checklist.

Code: M06.0A
Description: Rheumatoid arthritis without rheumatoid factor, other specified site
HCC (V28): HCC 93 — Rheumatoid Arthritis and Other Specified Inflammatory Rheumatic Disorders
RAF: 0.617
Billable: Yes
Payment year: 2026

HCC Category Mapping

V28HCC 93, Rheumatoid Arthritis and Other Specified Inflammatory Rheumatic Disorders

0.617

V24HCC 40, Rheumatoid Arthritis and Inflammatory Connective Tissue Disease

0.421

ESRDHCC 40, Rheumatoid Arthritis and Inflammatory Connective Tissue Disease

0.058

RxHCCHCC 83, Rheumatoid Arthritis and Inflammatory Connective Tissue Disease

0.222

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 M06.0A in the Code Book — tabular path, V28 RAF, and MEAT checklist →

MEAT Criteria for M06.0A

For M06.0A 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 M06.0A 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

M06.0A is the ICD-10-CM diagnosis code for rheumatoid arthritis without rheumatoid factor, other specified site. Rheumatoid arthritis without the typical blood marker affecting a joint site not covered by the other specific codes. M06.0A sits in the ICD-10-CM chapter for diseases of the musculoskeletal system and connective tissue (m00-m99), within the section covering inflammatory polyarthropathies (m05-m14).

Under the CMS-HCC V28 risk adjustment model, M06.0A maps to Rheumatoid Arthritis and Other Specified Inflammatory Rheumatic Disorders (HCC 93) with a community, non-dual, aged base RAF weight of 0.617. Under the older CMS-HCC V24 model, M06.0A maps to Rheumatoid Arthritis and Inflammatory Connective Tissue Disease (HCC 40) with a community, non-dual, aged base RAF weight of 0.421. 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.

Clearly document the specific anatomical site affected in the medical record. Because M06.0A 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 M06.0A sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•Clearly document the specific anatomical site affected in the medical record
•Use this code only when the affected site does not fit into the standard categories (shoulder, elbow, wrist, hip, knee, ankle, foot, vertebrae, or multiple sites)

Clinical Significance

Seronegative rheumatoid arthritis affecting other specified sites indicates RA involvement in joints not covered by other specific anatomical codes. This diagnosis requires careful documentation to support unusual or atypical joint involvement in chronic inflammatory arthritis.