Z28.9 – Immunization not carried out for unspecified reason
ICD-10-CM 2027 diagnosis code · Persons with potential health hazards related to communicable diseases
- Code
Z28.9(claims format:Z289)- Description
- Immunization not carried out for unspecified reason
- Billable
- Yes – valid for HIPAA-covered transactions
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 21. Factors influencing health status and contact with health services (Z00-Z99)
- Block
- Z20-Z29 Persons with potential health hazards related to communicable diseases
- Parent codes
- Z28
Notes inherited from parent codes
Instructional notes at a category or block level apply to every code below it.
Z28 – Immunization not carried out and underimmunization status
- vaccination not carried out
- , if applicable, encounter for immunization safety counseling (Z71.85)
Index terms for Z28.9
Entries in the ICD-10-CM alphabetic index that lead to this code:
Related codes in Z28
- Z28.0 – Immunization not carried out because of contraindicationHeader
- Z28.1 – Immunization not carried out because of patient decision for reasons of belief or group pressureBillable
- Z28.2 – Immunization not carried out because of patient decision for other and unspecified reasonHeader
- Z28.3 – Underimmunization statusHeader
- Z28.8 – Immunization not carried out for other reasonHeader
Frequently asked questions
What is ICD-10 code Z28.9?
Z28.9 is the ICD-10-CM code for immunization not carried out for unspecified reason, in the block Z20-Z29 (Persons with potential health hazards related to communicable diseases).
Is Z28.9 a billable code?
Yes. Z28.9 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.
What category does Z28.9 belong to?
It belongs to category Z28 – Immunization not carried out and underimmunization status.
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.