ICD-10-CM 2027 diagnosis code
Z28.1Immunization not carried out because of patient decision for reasons of belief or group pressure
Z28.1 is a valid, billable ICD-10-CM code for immunization not carried out because of patient decision for reasons of belief or group pressure. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.Short description: Immuniz not crd out because of patient belief/grp pressr
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About Z28.1
Z28.1 is the ICD-10-CM diagnosis code for immunization not carried out because of patient decision for reasons of belief or group pressure. It belongs to category Z28 (immunization not carried out and underimmunization status), block Z20-Z29 (persons with potential health hazards related to communicable diseases) and chapter 21 (factors influencing health status and contact with health services). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within Z28 (immunization not carried out and underimmunization status), Z28.1 is specifically for immunization not carried out because of patient decision for reasons of belief or group pressure. Related codes cover immunization not carried out because of contraindication (Z28.0), immunization not carried out because of patient decision for other and unspecified reason (Z28.2), underimmunization status (Z28.3), immunization not carried out for other reason (Z28.8) and immunization not carried out for unspecified reason (Z28.9).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 795 (Normal Newborn, relative weight 0.2022) and DRG 951 (Other Factors Influencing Health Status, relative weight 0.5577), in MDC 15 (Newborns and Other Neonates with Conditions Originating in the Perinatal Period) and MDC 23 (Factors Influencing Health Status and Other Contacts with Health Services), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It is not acceptable as the principal diagnosis for an inpatient stay; it may be reported as a secondary diagnosis.
It is exempt from present-on-admission (POA) reporting, so no POA indicator is required.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as V64.07 (vaccination not carried out for religious reasons).
Coding notes
- Immunization not carried out because of religious belief
Notes that apply from higher levels
Instructions written at a parent level also apply to Z28.1.
› From Z28 Immunization not carried out and underimmunization status
- vaccination not carried out
- , if applicable, encounter for immunization safety counseling (Z71.85)
Broader instructions also apply from Chapter 21: Factors influencing health status and contact with health services.
Alphabetic index entries
3 entriesTerms in the official ICD-10-CM index that lead to Z28.1.
Codes whose notes reference Z28.1
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 15 · Newborns and Other Neonates with Conditions Originating in the Perinatal Period
MDC 23 · Factors Influencing Health Status and Other Contacts with Health Services
ICD-9-CM equivalent
Converter →- V64.07Vaccination not carried out for religious reasonsexact
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about Z28.1
Is Z28.1 billable?
- Yes. Z28.1 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can Z28.1 be used as a principal diagnosis?
- No. It is not acceptable as the principal diagnosis for an inpatient stay; it may be reported as a secondary diagnosis.
Is Z28.1 a CC or MCC?
- No. Z28.1 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does Z28.1 group to?
- Z28.1 is used in the MS-DRG v44.0 logic for MS-DRG 795 (Normal Newborn) and MS-DRG 951 (Other Factors Influencing Health Status). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.