Z28.31 — Underimmunization for COVID-19 status
Is Z28.31 billable?
No — Z28.31 is a non-billable header code. Z28.31 groups more specific codes and cannot be submitted on a claim. A valid ICD-10-CM code must be reported at the highest level of specificity available in its branch. Select one of the 2 billable codes beneath Z28.31.
Billable codes under this header
Z28.31 at a glance
| Code | Z28.31 |
|---|---|
| Description | Underimmunization for COVID-19 status |
| Billable | No — header code |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
How is Z28.31 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to Z28.31. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Delinquent immunization status › COVID-19
- Underimmunization status › COVID-19
- Status › delinquent immunization › COVID-19 (post)
- Status › underimmunization › COVID-19 (post)
Note
- These codes should not be used for individuals who are not eligible for the COVID-19 vaccines, as determined by the healthcare provider.
Use additional code — inherited from Z28.3
Report an additional code alongside Z28.31 to fully describe the condition. Z28.31 is sequenced first.
- 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-)
Code also — inherited from Z28
Two codes may be needed to describe the condition fully. Whether Z28.31 is sequenced first depends on the reason for the encounter.
- , if applicable, encounter for immunization safety counseling (Z71.85)
What codes fall under Z28.31? (2)
How long has Z28.31 existed?
Z28.31 first appears in FY2023.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.