All ICD10 Codes

Z28.3

Non-Billable
ChapterZ00–Z99
Ranksubcategory
Official Description

Underimmunization status

Use a more specific code (1 billable, 1 non-billable)
Z28.31Underimmunization for COVID-19 statushas subcodesZ28.39Other underimmunization status
Metadata & Insights
  • •Non-billable category (requires more specific sub-code).
  • •Chapter 21: Factors Influencing Health Status and Contact with Health Services (Z00-Z99).

Instructional Notes

Use Additional Code
  • code, if applicable, to identify:
  • immunization not carried out because of contraindication (Z28.0-)
  • immunization not carried out because of patient decision for other and unspecified reason (Z28.2-)
  • immunization not carried out because of patient decision for reasons of belief or group pressure (Z28.1)
  • immunization not carried out for other reason (Z28.8-)
General instructions are available for the parent sections:
View Z28 Notes

Clinical Hierarchy

BillableHas subcodes
CH21Factors influencing health status and contact with health services (Z00-Z99)
Z20-Z29Persons with potential health hazards related to communicable diseases (Z20-Z29)
Z28Immunization not carried out and underimmunization status
Z28.3Underimmunization statusNot billable
Z28.31Underimmunization for COVID-19 statusSubcodes
Z28.39Other underimmunization statusBillable

Applicable Ancestor Context

The following parent sections contain instructions or notes that apply to Z28.3:

categoryZ28
Immunization not carried out and underimmunization status
View context instructions

Code History

  • FY 04/01/22: Superseded by Z28.310
  • FY 04/01/22: Superseded by Z28.311
  • FY 04/01/22: Superseded by Z28.39

MS-DRG Classification

2026

No direct MS-DRG triggers identified.

Cross Reference

Find Procedures (ICD-10-PCS)

Find surgical and procedural codes related to Underimmunization status.

Search PCS Codes