Is ICD-10-CM code D66 billable?

Yes, D66 (Hereditary factor VIII deficiency) is a billable ICD-10-CM diagnosis code, valid for reimbursement on HIPAA-covered transactions for FY2026.

What chapter does ICD-10-CM code D66 belong to?

D66 belongs to Chapter 3 of the ICD-10-CM tabular list: D50–D89 (Diseases of the Blood and Blood-Forming Organs).

D66

Billable

ChapterD50–D89

Rankcategory

Description

Hereditary factor VIII deficiency

About ICD-10-CM code D66

D66 is the ICD-10-CM diagnosis code for Hereditary factor VIII deficiency. It sits in D50-D89 Diseases of the Blood and Blood-Forming Organs, within Coagulation defects, purpura and other hemorrhagic conditions (D65-D69). As a billable code, D66 can be reported for reimbursement.

Metadata & Insights

•Billable/specific code (valid for reimbursement).
•Chapter 3: Diseases of the Blood and Blood-Forming Organs (D50-D89).

CH3 Parent Instructions

Excludes2(Not included here. Code separately if applicable.)

autoimmune disease (systemic) NOS (M35.9)
certain conditions originating in the perinatal period (P00-P96)
complications of pregnancy, childbirth and the puerperium (O00-O9A)
congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
endocrine, nutritional and metabolic diseases (E00-E88)
human immunodeficiency virus [HIV] disease (B20)
injury, poisoning and certain other consequences of external causes (S00-T88)
neoplasms (C00-D49)
symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Instructional Notes

Includes

Classical hemophilia
Deficiency factor VIII (with functional defect)
Hemophilia NOS
Hemophilia A

Excludes1(Not coded here. Use a different code.)

factor VIII deficiency with vascular defect (D68.0-)

Clinical Hierarchy

BillableHas subcodes

CH3Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (D50-D89)

D65-D69Coagulation defects, purpura and other hemorrhagic conditions (D65-D69)

D66Hereditary factor VIII deficiencyBillable

Applicable Ancestor Context

The following parent sections contain instructions or notes that apply to D66:

chapterCH3

Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (D50-D89)

View context instructions

MS-DRG Classification

2026 v43.1

This code is grouped within the following Diagnosis Related Group(s) for clinical reimbursement:

DRG 813

Coagulation Disorders

Cross Reference

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