Z23 — Encounter for immunization
Z23 is a billable, specific ICD-10-CM code for encounter for immunization. It is valid for submission on a claim.
Code first
The underlying condition must be sequenced before this code.
- any routine childhood examination
Code also
Both codes may be needed to describe the encounter fully. Sequencing depends on the reason for the visit.
- , if applicable, encounter for immunization safety counseling (Z71.85)
Notes
Additional guidance from the ICD-10-CM tabular list.
- procedure codes are required to identify the types of immunizations given
Risk adjustment
Z23 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
Z23 is named in 1 Medicare coverage policy — 1 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A54767Billing and Coding: Medicare Preventive Coverage for Certain Vaccines
How Z23 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to Z23.
- Immunization›encounter for
- Prophylactic›vaccination
- Vaccination›encounter for
- Admission›prophylactic›vaccination
Questions about Z23
- Is Z23 a billable ICD-10-CM code?
- Yes. Z23 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does Z23 sit in the tabular list?
- Factors influencing health status and contact with health services (Z00-Z99), in the block Persons with potential health hazards related to communicable diseases (Z20-Z29).