Z23Billable
Encounter for immunization
- Chapter
- 21. Factors influencing health status and contact with health services
- Category
- Z23
- Effective date
- October 1, 2026
Frequently asked questions
What is ICD-10 code Z23?
Z23 is an ICD-10-CM diagnosis code for Encounter for immunization.
Is Z23 a billable code?
Yes. Z23 is billable and specific enough to be used on a claim.
What ICD-10-CM chapter is Z23 in?
Z23 falls under Chapter 21: Factors influencing health status and contact with health services.
When did Z23 become effective?
Z23 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.
ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.