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  6. 2024 ICD-10-CM Code Z28.3

2024 ICD-10-CM Diagnosis Code Z28.3

Underimmunization status

ICD-10-CM Code:
Z28.3
ICD-10 Code for:
Underimmunization status
Is Billable?
Not Valid for Submission
Code Navigator:

Code Classification

  • Factors influencing health status and contact with health services
    (Z00–Z99)
    • Persons with potential health hazards related to communicable diseases
      (Z20-Z29)
      • Immunization not carried out and underimmunization status
        (Z28)

Z28.3 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of underimmunization status. The code is not specific and is NOT valid for the year 2024 for the submission of HIPAA-covered transactions. Category or Header define the heading of a category of codes that may be further subdivided by the use of 4th, 5th, 6th or 7th characters.

Specific Coding Applicable to Underimmunization status

Non-specific codes like Z28.3 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10-CM codes with a higher level of specificity when coding for underimmunization status:

  • Z28.31 for Underimmunization for COVID-19 status - NON-BILLABLE CODE

  • Use Z28.310 for Unvaccinated for COVID-19 - BILLABLE CODE

  • Use Z28.311 for Partially vaccinated for COVID-19 - BILLABLE CODE

  • Use Z28.39 for Other underimmunization status - BILLABLE CODE

Clinical Classification

Tabular List of Diseases and Injuries

The following annotation back-references are applicable to this diagnosis code. The Tabular List of Diseases and Injuries is a list of ICD-10-CM codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more.


Use Additional Code

Use Additional Code
The “use additional code” indicates that a secondary code could be used to further specify the patient’s condition. This note is not mandatory and is only used if enough information is available to assign an 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

Convert Z28.3 to ICD-9-CM

  • ICD-9-CM Code: V15.83 - Hx underimmunizn status

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.