ICD-10 Z23
Billable / SpecificEncounter for immunization
About ICD-10-CM Z23
ICD-10-CM code Z23 represents Encounter for immunization. This is a billable/specific code in the Factors Influencing Health Status chapter (block Z23). The 2026 edition of ICD-10-CM Z23 became effective on October 1, 2025.
Coding Notes
Code Also
- , if applicable, encounter for immunization safety counseling (Z71.85)
Code First
- any routine childhood examination
Medicare LCD Coverage for Z23
Local Coverage Determinations (LCDs) from CMS MACs that list Z23 as a covered diagnosis.
Showing top 10 of 47 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing Z23.
3 Aetna
2 Cigna
1 Medicare
CPT Codes Commonly Billed with Z23
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
- 99202 New patient office visit — fever, headache, abdominal pain, cough, dyspnea, fatigue, dizziness, limb pain, nausea, routine exam, URI, UTI, pharyngitis, otitis, chest pain, weight loss Primary Care
- 99211 Established patient minimal visit — BP check, medication refill, nurse visit, immunization admin, post-op follow-up, injury follow-up Primary Care
Convert Z23 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 |
|---|---|---|
| Z23 | V059 | 10000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To Z23
Other codes in section Z20-Z29 (Persons with potential health hazards related to communicable diseases).
ICD-10 Z23, Billing FAQ
Is ICD-10 code Z23 billable? +
Yes, Z23 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What CPT codes are commonly billed with Z23? +
Procedures frequently paired with Z23 include: 99202, 99211.
What ICD-9 codes does Z23 map to? +
Per CMS GEMs, Z23 maps to ICD-9 codes: V059. 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 June 1, 2026.
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