Z28.3

Underimmunization status

Not billable — category only FY2026 2025-10-01 → 2026-09-30

Instructional notes 10

Z28code

Includes

Code also

Use additional code

code, if applicable, to identify:
immunization not carried out because of contraindication (Z28.0-)Z28.0-Z28.0-
immunization not carried out because of patient decision for other and unspecified reason (Z28.2-)Z28.2-Z28.2-
immunization not carried out because of patient decision for reasons of belief or group pressure (Z28.1)Z28.1 Z28.1
immunization not carried out for other reason (Z28.8-)Z28.8-Z28.8-

Notes

Z codes represent reasons for encounters. A corresponding procedure code must accompany a Z code if a procedure is performed. Categories Z00-Z99 are provided for occasions when circumstances other than a disease, injury or external cause classifiable to categories A00-Y89 are recorded as 'diagnoses' or 'problems'. This can arise in two main ways:Z00-Z99 A00-Y89
(a) When a person who may or may not be sick encounters the health services for some specific purpose, such as to receive limited care or service for a current condition, to donate an organ or tissue, to receive prophylactic vaccination (immunization), or to discuss a problem which is in itself not a disease or injury.
(b) When some circumstance or problem is present which influences the person's health status but is not in itself a current illness or injury.

Index entries leading here filed at null

No alphabetic index entry points at this code.

Alongside this code 5 same parent — Z28

Subordinate codes 2

Additional references

AHA Coding Clinic® Licence required

Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.

Maps to no condition category in any loaded model.

Presence is a property of the code. Untick a model to hide it everywhere.

Present FY2024–FY2027.