What is ICD-10 code D56.5?

D56.5 is the ICD-10-CM diagnosis code for Hemoglobin E-beta thalassemia. A blood disorder where a person inherits hemoglobin E from one parent and a thalassemia gene from the other, causing mild to moderate anemia and abnormal red blood cells. D56.5 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. D56.5 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. D56.5 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. D56.5 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.

What is the V28 vs V24 difference for D56.5?

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 D56.5, V28 maps to Sickle Cell Disorders and Thalassemia at RAF 0.607 while V24 mapped to Coagulation Defects and Other Specified Hematological Disorders at RAF 0.209. Both models can still appear in legacy data and in payer-specific lookback periods.

What should coders know when reporting D56.5?

Document whether the patient has hemoglobin E trait or disease to ensure accurate code selection Verify the specific type of beta thalassemia component (thalassemia major, minor, or intermedia) when documented Because D56.5 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.

D56.5 ICD-10 Code: Hemoglobin E-beta thalassemia

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 lookupD56.5Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (D50-D89) / Hemolytic anemias (D55-D59)

D56.5

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

Hemoglobin E-beta thalassemia

A blood disorder where a person inherits hemoglobin E from one parent and a thalassemia gene from the other, causing mild to moderate anemia and abnormal red blood cells.

Buddy Insight

Hemoglobin E-beta thalassemia is a compound heterozygous condition where one parent contributes a hemoglobin E gene and the other a beta thalassemia gene.

CMS-HCC V28

Mapped

HCC 108

Sickle Cell Disorders and Tha...

RAF 0.607

CMS-HCC V24

Mapped

HCC 48

Coagulation Defects and Other...

RAF 0.209

ACA/HHS

Not risk-adjusted for this model/period.

RAF 0

ESRD/PACE

Mapped

HCC 48

Coagulation Defects and Other...

RAF 0.0

RXHCC

Not risk-adjusted for this model/period.

RAF 0

Code Trumping

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Compare selected patient codes to show trumped or trumps impact.

Code Book Path

Official

D56Thalassemia

D56.5Hemoglobin E-beta thalassemia

Inclusion Terms

Official

ICD-10-CM does not list inclusion terms for D56.5 in this effective period.

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for D56.5 in this effective period.

Related Child Codes

Official

D56.0Alpha thalassemia

D56.1Beta thalassemia

D56.2Delta-beta thalassemia

D56.3Thalassemia minor

D56.4Hereditary persistence of fetal hemoglobin [HPFH]

Includes

Official

ICD-10-CM does not list Includes notes for D56.5 in this effective period.

Excludes 1

Official

beta thalassemia (D56.1)
beta thalassemia minor (D56.3)
beta thalassemia trait (D56.3)
delta-beta thalassemia (D56.2)
delta-beta thalassemia trait (D56.3)

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for D56.5 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for D56.5 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for D56.5 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Document the compound heterozygous state with hemoglobin electrophoresis showing hemoglobin E and elevated fetal hemoglobin, supported by genetic testing when available.

Specify clinical severity (mild, moderate, or severe/transfusion-dependent), hemoglobin levels, mean corpuscular volume, transfusion schedule, iron chelation therapy, and ferritin monitoring results.

Record complications including splenomegaly, iron overload, and endocrinopathies.

MEAT Support

HCC Buddy guidance

Document the compound heterozygous state with hemoglobin electrophoresis showing hemoglobin E and elevated fetal hemoglobin, supported by genetic testing when available.

Specify clinical severity (mild, moderate, or severe/transfusion-dependent), hemoglobin levels, mean corpuscular volume, transfusion schedule, iron chelation therapy, and ferritin monitoring results.

Record complications including splenomegaly, iron overload, and endocrinopathies.

Audit Caution

HCC Buddy guidance

Under V28, this maps to HCC 108 (RAF 0.607), making accurate identification important for risk adjustment. Clinical severity varies dramatically based on the specific beta thalassemia mutation, so documentation of clinical phenotype is essential. Do not code hemoglobin E trait alone as D56.5 -

this code requires both the hemoglobin E variant and a co-inherited beta thalassemia gene. Ensure the provider documents both genetic components.

Common Mistakes

HCC Buddy guidance

D56.5 vs. D56.1 (Beta thalassemia) -

D56.5 is specifically for the combination of hemoglobin E plus beta thalassemia, not beta thalassemia alone. D56.5 vs. D58.2 (Other hemoglobinopathies) -

hemoglobin E disease without thalassemia co-inheritance is coded separately. D56.5 vs. D57.40 (Sickle-cell thalassemia) -

different hemoglobin variant combined with thalassemia.

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 D56.5 an HCC code?

Yes. D56.5 maps to Sickle Cell Disorders and Thalassemia under the CMS-HCC V28 risk adjustment model (and Coagulation Defects and Other Specified Hematological Disorders under V24).

HCC Category Mapping

V28HCC 108, Sickle Cell Disorders and Thalassemia

0.607

V24HCC 48, Coagulation Defects and Other Specified Hematological Disorders

0.209

ESRDHCC 48, Coagulation Defects and Other Specified Hematological Disorders

0.000

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 D56.5

For D56.5to 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 D56.5 during that encounter, not just copy-forwarded from a problem list.

What This Code Means

D56.5 is the ICD-10-CM diagnosis code for hemoglobin e-beta thalassemia. A blood disorder where a person inherits hemoglobin E from one parent and a thalassemia gene from the other, causing mild to moderate anemia and abnormal red blood cells. D56.5 sits in the ICD-10-CM chapter for diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (d50-d89), within the section covering hemolytic anemias (d55-d59).

Under the CMS-HCC V28 risk adjustment model, D56.5 maps to Sickle Cell Disorders and Thalassemia (HCC 108) with a community, non-dual, aged base RAF weight of 0.607. Under the older CMS-HCC V24 model, D56.5 maps to Coagulation Defects and Other Specified Hematological Disorders (HCC 48) with a community, non-dual, aged base RAF weight of 0.209. 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.

Document whether the patient has hemoglobin E trait or disease to ensure accurate code selection. Because D56.5 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 D56.5 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•Document whether the patient has hemoglobin E trait or disease to ensure accurate code selection
•Verify the specific type of beta thalassemia component (thalassemia major, minor, or intermedia) when documented

Clinical Significance

Hemoglobin E-beta thalassemia is a compound heterozygous condition where one parent contributes a hemoglobin E gene and the other a beta thalassemia gene. It is the most common form of severe thalassemia worldwide, particularly prevalent in Southeast Asian populations. Clinical severity varies from asymptomatic to transfusion-dependent, depending on the beta thalassemia mutation type (beta-zero vs. beta-plus), making accurate characterization essential for management planning.

Documentation Requirements

✓Document the compound heterozygous state with hemoglobin electrophoresis showing hemoglobin E and elevated fetal hemoglobin, supported by genetic testing when available.
✓Specify clinical severity (mild, moderate, or severe/transfusion-dependent), hemoglobin levels, mean corpuscular volume, transfusion schedule, iron chelation therapy, and ferritin monitoring results.
✓Record complications including splenomegaly, iron overload, and endocrinopathies.

Excludes 1, Do NOT code together

beta thalassemia (D56.1)
beta thalassemia minor (D56.3)
beta thalassemia trait (D56.3)
delta-beta thalassemia (D56.2)
delta-beta thalassemia trait (D56.3)
hemoglobin E disease (D58.2)
other hemoglobinopathies (D58.2)
sickle-cell beta thalassemia (D57.4-)

Commonly Confused Codes

•D56.5 vs. D56.1 (Beta thalassemia) -
•D56.5 is specifically for the combination of hemoglobin E plus beta thalassemia, not beta thalassemia alone. D56.5 vs. D58.2 (Other hemoglobinopathies) -
•hemoglobin E disease without thalassemia co-inheritance is coded separately. D56.5 vs. D57.40 (Sickle-cell thalassemia) -
•different hemoglobin variant combined with thalassemia.