ICD-10 B20
Billable / Specific HCC v28: 1 CCHuman immunodeficiency virus [HIV] disease
About ICD-10-CM B20
ICD-10-CM code B20 represents Human immunodeficiency virus [HIV] disease. This is a billable/specific code in the Infectious and Parasitic Diseases chapter (block B20). The 2026 edition of ICD-10-CM B20 became effective on October 1, 2025.
Coding Tips for B20
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
B20 is a CMS-HCC v28 risk-adjustment code (category 1). To count for the patient Risk Adjustment Factor (RAF), document the diagnosis with MEAT language each calendar year: Monitored, Evaluated, Assessed, Treated. A diagnosis on the problem list alone does not satisfy CMS RADV audit standards. Include the diagnosis in the assessment with current status and current treatment plan.
B20 is designated CC for MS-DRG grouping. On inpatient claims, this code can shift the DRG to the with-CC variant when documented as a present-on-admission secondary diagnosis. Hospital CDI programs flag CC opportunities during chart review. Failure to capture this code may leave 30 to 80 percent of the inpatient stay revenue unrealized.
Type 1 Excludes
Pure excludes, these codes can never be coded together with B20. The conditions are mutually exclusive (e.g., congenital vs acquired forms).
- asymptomatic human immunodeficiency virus [HIV] infection status (Z21)
- exposure to HIV virus (Z20.6)
- inconclusive serologic evidence of HIV (R75)
Includes
- acquired immune deficiency syndrome [AIDS]
- AIDS-related complex [ARC]
- HIV infection, symptomatic
Use Additional Code
When coding B20, also report these additional codes when applicable.
- code(s) to identify all manifestations of HIV infection
Coding Notes
Code First
- Human immunodeficiency virus [HIV] disease complicating pregnancy, childbirth and the puerperium, if applicable (O98.7-)
Medicare Advantage HCC Impact
Capture this diagnosis annually for accurate risk adjustment. Missed HCC captures are the #1 revenue leak in Medicare Advantage risk programs.
Inpatient DRG Impact, CC
codes Human immunodeficiency virus [HIV] disease. As a Complication/Comorbidity (CC), this contributes to DRG severity adjustment when documented alongside the principal diagnosis.
Medicare LCD Coverage for B20
Local Coverage Determinations (LCDs) from CMS MACs that list B20 as a covered diagnosis.
Showing top 10 of 1,299 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing B20.
3 Aetna
5 Cigna
5 Medicare
CPT Codes Commonly Billed with B20
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
- 92235 CMS LCD: Billing and Coding: Ophthalmic Angiography (Fluorescein and Indocyanine Green) CMS LCD
- 92240 CMS LCD: Billing and Coding: Ophthalmic Angiography (Fluorescein and Indocyanine Green) CMS LCD
- 0031U CMS LCD: Billing and Coding: Pharmacogenomics Testing CMS LCD
- 0173U CMS LCD: Billing and Coding: Pharmacogenomics Testing CMS LCD
- 0423U CMS LCD: Billing and Coding: Pharmacogenomics Testing CMS LCD
- 81407 CMS LCD: Billing and Coding: Pharmacogenomics Testing CMS LCD
- 0349U CMS LCD: Billing and Coding: Pharmacogenomics Testing CMS LCD
- 81408 CMS LCD: Billing and Coding: Pharmacogenomics Testing CMS LCD
- 0175U CMS LCD: Billing and Coding: Pharmacogenomics Testing CMS LCD
- 0032U CMS LCD: Billing and Coding: Pharmacogenomics Testing CMS LCD
Convert B20 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| B20 | 042 | 00000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
ICD-10 B20, Billing FAQ
Is ICD-10 code B20 billable? +
Yes, B20 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What codes are Type 1 Excludes for B20? +
Type 1 Excludes (never code together with B20): asymptomatic human immunodeficiency virus [HIV] infection status (Z21); exposure to HIV virus (Z20.6); inconclusive serologic evidence of HIV (R75)
Does B20 affect Medicare Advantage HCC risk adjustment? +
Yes. B20 maps to CMS-HCC v28 category 1. Capture this diagnosis annually for accurate Medicare Advantage risk score.
Is B20 a CC or MCC for inpatient DRG? +
Yes, this code is designated as CC. Documenting as a secondary diagnosis on inpatient claims can shift the DRG to a higher-weighted category.
What CPT codes are commonly billed with B20? +
Procedures frequently paired with B20 include: 92235, 92240, 0031U, 0173U, 0423U.
What ICD-9 codes does B20 map to? +
Per CMS GEMs, B20 maps to ICD-9 codes: 042. Useful for legacy data review and historical claim analysis.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on July 16, 2026.
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