ICD-10-CM · Chapter 3 · D50-D89
D66 Hereditary factor VIII deficiency
Includes
- Classical hemophilia
- Deficiency factor VIII (with functional defect)
- Hemophilia NOS
- Hemophilia A
Excludes 1 (cannot be coded together)
- factor VIII deficiency with vascular defect (D68.0-)
This category is a complete, billable diagnosis code.
No additional specificity is required — submit D66 directly on claims and documentation without a subcode extension.
Plain-language term for this code
The following entry in the US Medical Glossary corresponds to ICD-10-CM category D66:
- Hemophilia — Hemofilia
Last reviewed: September 2026