FY2027 ICD-10-CM reference
Z21: Asymptomatic human immunodeficiency virus [HIV] infection status
By the HCC Buddy Coding Team
The official ICD-10-CM descriptor is Asymptomatic human immunodeficiency virus [HIV] infection status. 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
Mapped- HCC 1HIV/AIDSCoefficient 0.301 (CNA, PY2027)
CMS-HCC V24
Not used by CMSESRD
Mapped- HCC 1HIV/AIDSCoefficient 0.122 (Dialysis CE, PY2027)
RxHCC
Mapped- HCC 1HIV/AIDSCoefficient 8.304 (MA-PD CE non-low aged, PY2027)
PACE (CMS-HCC V22 component)
Mapped- HCC 1HIV/AIDS
PACE ESRD (ESRD V21 component)
Mapped- HCC 1HIV/AIDS
PACE RxHCC (2018/2019 component)
Mapped- HCC 1HIV/AIDS
Jan 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.
Instructional note
Z codes represent reasons for encounters. A corresponding procedure code must accompany a Z code if a procedure is performed. Categories Z00-Z99 are provided for occasions when circumstances other than a disease, injury or external cause classifiable to categories A00-Y89 are recorded as 'diagnoses' or 'problems'. This can arise in two main ways:
Source: Z00-Z99 (chapter, inherited).
Instructional note
(a) When a person who may or may not be sick encounters the health services for some specific purpose, such as to receive limited care or service for a current condition, to donate an organ or tissue, to receive prophylactic vaccination (immunization), or to discuss a problem which is in itself not a disease or injury.
Source: Z00-Z99 (chapter, inherited).
Instructional note
(b) When some circumstance or problem is present which influences the person's health status but is not in itself a current illness or injury.
Source: Z00-Z99 (chapter, inherited).
Instructional note
HIV positive NOS
Source: Z21 (category, direct).
Code first
Human immunodeficiency virus [HIV] disease complicating pregnancy, childbirth and the puerperium, if applicable (O98.7-)
Source: Z21 (category, direct).
Excludes1
acquired immunodeficiency syndrome (B20)
Source: Z21 (category, direct).
Excludes1
contact with human immunodeficiency virus [HIV] (Z20.6)
Source: Z21 (category, direct).
Excludes1
exposure to human immunodeficiency virus [HIV] (Z20.6)
Source: Z21 (category, direct).
Excludes1
human immunodeficiency virus [HIV] disease (B20)
Source: Z21 (category, direct).
Excludes1
inconclusive laboratory evidence of human immunodeficiency virus [HIV] (R75)
Source: Z21 (category, direct).
Compare the FY2027 additions, removals and billable-status changes
What does Z21 mean in FY2027?
The official ICD-10-CM descriptor is Asymptomatic human immunodeficiency virus [HIV] infection status. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Is Z21 billable in FY2027?
The FY2027 order file marks Z21 as billable. Check the complete Tabular instructions and documentation before assigning it.
Does Z21 map to an HCC?
Oct to Dec 2026, PY2027: CMS-HCC V28 HCC 1 (HIV/AIDS); CMS-HCC V24: Not used by CMS; ESRD HCC 1 (HIV/AIDS); RxHCC HCC 1 (HIV/AIDS). 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