FY2027 ICD-10-CM reference
D66: Hereditary factor VIII deficiency
By the HCC Buddy Coding Team
The official ICD-10-CM descriptor is Hereditary factor VIII deficiency. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Billable code. Verified against the official FY2027 order file.
Oct to Dec 2026, PY2027
CMS-HCC V28
Depends on member age or sex- HCC 111Hemophilia, Male
- HCC 112Immune Thrombocytopenia and Specified Coagula...
Candidates: the category depends on member age or sex
- HCC 111 when male
- HCC 112 when female
- HCC 111: This code has a CMS sex requirement: applies to male members
- HCC 112: This code has a CMS sex requirement: applies to female members
CMS-HCC V24
Not used by CMSESRD
Depends on member age or sex- HCC 46Severe Hematological Disorders
- HCC 48Coagulation Defects and Other Specified Hemat...
Candidates: the category depends on member age or sex
- HCC 46: This code has a CMS sex requirement: applies to male members
- HCC 48: This code has a CMS sex requirement: applies to female members
RxHCC
No CMS categoryPACE (CMS-HCC V22 component)
Depends on member age or sex- HCC 46Severe Hematological Disorders
- HCC 48Coagulation Defects and Other Specified Hemat...
Candidates: the category depends on member age or sex
- HCC 46: This code has a CMS sex requirement: applies to male members
- HCC 48: This code has a CMS sex requirement: applies to female members
PACE ESRD (ESRD V21 component)
Depends on member age or sex- HCC 46Severe Hematological Disorders
- HCC 48Coagulation Defects and Other Specified Hemat...
Candidates: the category depends on member age or sex
- HCC 46: This code has a CMS sex requirement: applies to male members
- HCC 48: This code has a CMS sex requirement: applies to female members
PACE RxHCC (2018/2019 component)
No CMS categoryJan to Sep 2027, PY2028
CMS-HCC V28
Not published by CMSCMS-HCC V24
Not published by CMSESRD
Not published by CMSRxHCC
Not published by CMSPACE (CMS-HCC V22 component)
Not published by CMSPACE ESRD (ESRD V21 component)
Not published by CMSPACE RxHCC component
Not published by CMSOct to Dec 2026, BY2026
HHS-HCC
PendingJan to Sep 2027, BY2027
HHS-HCC
Not published by CMSFY2027 Tabular instructions
Instructions below include applicable chapter, section and parent-code notes. Each note identifies where it appears in the official source.
Excludes2
autoimmune disease (systemic) NOS (M35.9)
Source: D50-D89 (chapter, inherited).
Excludes2
certain conditions originating in the perinatal period (P00-P96)
Source: D50-D89 (chapter, inherited).
Excludes2
complications of pregnancy, childbirth and the puerperium (O00-O9A)
Source: D50-D89 (chapter, inherited).
Excludes2
congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
Source: D50-D89 (chapter, inherited).
Excludes2
endocrine, nutritional and metabolic diseases (E00-E88)
Source: D50-D89 (chapter, inherited).
Excludes2
human immunodeficiency virus [HIV] disease (B20)
Source: D50-D89 (chapter, inherited).
Excludes2
injury, poisoning and certain other consequences of external causes (S00-T88)
Source: D50-D89 (chapter, inherited).
Excludes2
neoplasms (C00-D49)
Source: D50-D89 (chapter, inherited).
Excludes2
symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Source: D50-D89 (chapter, inherited).
Instructional note
Classical hemophilia
Source: D66 (category, direct).
Instructional note
Deficiency factor VIII (with functional defect)
Source: D66 (category, direct).
Instructional note
Hemophilia NOS
Source: D66 (category, direct).
Instructional note
Hemophilia A
Source: D66 (category, direct).
Excludes1
factor VIII deficiency with vascular defect (D68.0-)
Source: D66 (category, direct).
Compare the FY2027 additions, removals and billable-status changes
What does D66 mean in FY2027?
The official ICD-10-CM descriptor is Hereditary factor VIII deficiency. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Is D66 billable in FY2027?
The FY2027 order file marks D66 as billable. Check the complete Tabular instructions and documentation before assigning it.
Does D66 map to an HCC?
Oct to Dec 2026, PY2027: CMS-HCC V28 depends on member age or sex: HCC 111 (Hemophilia, Male) and HCC 112 (Immune Thrombocytopenia and Specified Coagulation Defects and Hemorrhagic Conditions) (HCC 111: This code has a CMS sex requirement: applies to male members; HCC 112: This code has a CMS sex requirement: applies to female members); CMS-HCC V24: Not used by CMS; ESRD depends on member age or sex: HCC 46 (Severe Hematological Disorders) and HCC 48 (Coagulation Defects and Other Specified Hematological Disorders) (HCC 46: This code has a CMS sex requirement: applies to male members; HCC 48: This code has a CMS sex requirement: applies to female members); RxHCC: No CMS category. Jan to Sep 2027, PY2028: CMS-HCC V28: Not published by CMS; CMS-HCC V24: Not published by CMS; ESRD: Not published by CMS; RxHCC: Not published by CMS. Oct to Dec 2026, BY2026: HHS-HCC: Pending. Jan to Sep 2027, BY2027: HHS-HCC: Not published by CMS. Base coefficients are reference values, not a member total.
Source: CMS FY2027 ICD-10-CM order file. Payment model: CMS CY 2027 Rate Announcement. Read the FY2027 Official Guidelines.
Review the FY2026 April edition