ICD-10-CM 2027 diagnosis code

D56Thalassemia

Not billable — use a more specific code

D56 is a header code, so it can't be reported by itself. Choose one of the 8 more specific codes beneath it.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About D56

D56 is the ICD-10-CM diagnosis code for thalassemia. It belongs to block D55-D59 (hemolytic anemias) and chapter 3 (diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism). It is a header code, so it can't be reported by itself; one of its 8 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: D56.0 (thalassemia), D56.1 (thalassemia), D56.2 (thalassemia), D56.3 (minor), D56.4 ([HPFH]), D56.5 (thalassemia), D56.8 (thalassemias) and D56.9 (unspecified).

Don't report D56 together with the conditions in its Excludes1 note: sickle-cell thalassemia (D57.4-).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Specific codes under D56

Coding notes

Excludes1Not coded here — never report together with this code

sickle-cell thalassemia (D57.4-)

Notes that apply from higher levels

Instructions written at a parent level also apply to D56.

Broader instructions also apply from Chapter 3: Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism.

Codes whose notes reference D56

M36.3Code first

Code history

2016
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2021
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2023
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2025
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2027

FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
No changes since FY2016.

Common questions about D56

Is D56 billable?: No. D56 is a header code. Report one of its more specific subcodes instead.