ICD-10-CM · Chapter 21 · Z00-Z99
Z28 Immunization not carried out and underimmunization status
Includes
- vaccination not carried out
Code Also
- , if applicable, encounter for immunization safety counseling (Z71.85)
Subcodes
Subcodes are listed below for reference. Detail pages are not available for chapters 11–22.
| Code | Description | Billable |
|---|---|---|
| Z28..0 | Immunization not carried out because of contraindication | No |
| Z28..01 | Immunization not carried out because of acute illness of patient | Yes |
| Z28..02 | Immunization not carried out because of chronic illness or condition of patient | Yes |
| Z28..03 | Immunization not carried out because of immune compromised state of patient | Yes |
| Z28..04 | Immunization not carried out because of patient allergy to vaccine or component | Yes |
| Z28..09 | Immunization not carried out because of other contraindication | Yes |
| Z28..1 | Immunization not carried out because of patient decision for reasons of belief or group pressure | Yes |
| Z28..2 | Immunization not carried out because of patient decision for other and unspecified reason | No |
| Z28..20 | Immunization not carried out because of patient decision for unspecified reason | Yes |
| Z28..21 | Immunization not carried out because of patient refusal | Yes |
| Z28..29 | Immunization not carried out because of patient decision for other reason | Yes |
| Z28..3 | Underimmunization status | No |
| Z28..31 | Underimmunization for COVID-19 status | No |
| Z28..310 | Unvaccinated for COVID-19 | Yes |
| Z28..311 | Partially vaccinated for COVID-19 | Yes |
| Z28..39 | Other underimmunization status | Yes |
| Z28..8 | Immunization not carried out for other reason | No |
| Z28..81 | Immunization not carried out due to patient having had the disease | Yes |
| Z28..82 | Immunization not carried out because of caregiver refusal | Yes |
| Z28..83 | Immunization not carried out due to unavailability of vaccine | Yes |
| Z28..89 | Immunization not carried out for other reason | Yes |
| Z28..9 | Immunization not carried out for unspecified reason | Yes |
Last reviewed: September 2026