Z28Non-billableSave
Z28 - Immunization not carried out and underimmunization status
ICD-10-CM Chapter 21: Factors influencing health status and contact with health services · Z20-Z29 Persons with potential health hazards related to communicable diseases (Z20-Z29) · Top-level category · FY2027
Coding Guidance
Z28 is a non-billable heading. Report one of the 6 more specific codes below.
Includes, Excludes and Coding Notes
IncludesFrom Z28
Conditions this code covers.
- vaccination not carried out
Code AlsoFrom Z28
Report an additional code when both conditions apply.
- , if applicable, encounter for immunization safety counseling (Z71.85)
NotesFrom Chapter Z00-Z99
Instructional notes from the ICD-10-CM tabular list.
- 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:
- (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.
More Specific Codes (6)
Z28.0Immunization not carried out because of contraindicationCategory→Z28.1Immunization not carried out because of patient decision for reasons of belief or group pressureBillable→Z28.2Immunization not carried out because of patient decision for other and unspecified reasonCategory→Z28.3Underimmunization statusCategory→Z28.8Immunization not carried out for other reasonCategory→Z28.9Immunization not carried out for unspecified reasonBillable→
Related condition guides
Documentation requirements, coding pitfalls and FAQs for conditions coded with Z28.
Chapter Information
Chapter 21: Factors influencing health status and contact with health services
Range: Z00-Z99
View full chapterRelated ICD-10 Codes
More specific codes for Z28
Immunization not carried out because of contraindication
Z28.0›
Immunization not carried out because of patient decision for reasons of belief or group pressureZ28.1›
Immunization not carried out because of patient decision for other and unspecified reasonZ28.2›
Underimmunization statusZ28.3›
Immunization not carried out for other reasonZ28.8›
Immunization not carried out for unspecified reasonZ28.9›
Other categories in this chapter
Codes at the same level as Z28
- Encounter for general examination without complaint, suspected or reported diagnosisZ00
- Encounter for other special examination without complaint, suspected or reported diagnosisZ01
- Encounter for administrative examinationZ02
- Encounter for medical observation for suspected diseases and conditions ruled outZ03
- Encounter for examination and observation for other reasonsZ04
- Encounter for observation and evaluation of newborn for suspected diseases and conditions ruled outZ05
- Encounter for follow-up examination after completed treatment for malignant neoplasmZ08
- Encounter for follow-up examination after completed treatment for conditions other than malignant neoplasmZ09
- Encounter for screening for infectious and parasitic diseasesZ11
- Encounter for screening for malignant neoplasmsZ12
- Encounter for screening for other diseases and disordersZ13
- Genetic carrierZ14
- Genetic susceptibility to diseaseZ15
- Resistance to antimicrobial drugsZ16
- Estrogen, and other hormones and factors receptor statusZ17
- Retained foreign body fragmentsZ18
- Hormone sensitivity malignancy statusZ19
- Contact with and (suspected) exposure to communicable diseasesZ20
- Asymptomatic human immunodeficiency virus [HIV] infection statusZ21
- Carrier of infectious diseaseZ22
- Encounter for immunizationZ23
- Encounter for other prophylactic measuresZ29
- Encounter for contraceptive managementZ30
- Encounter for procreative managementZ31
- Encounter for pregnancy test and childbirth and childcare instructionZ32
- Pregnant stateZ33
- Encounter for supervision of normal pregnancyZ34
- Encounter for antenatal screening of motherZ36
- Outcome of deliveryZ37
- Liveborn infants according to place of birth and type of deliveryZ38
- Encounter for maternal postpartum care and examinationZ39
- Weeks of gestationZ3A
- Encounter for prophylactic surgeryZ40
- Encounter for procedures for purposes other than remedying health stateZ41
- Encounter for plastic and reconstructive surgery following medical procedure or healed injuryZ42
- Encounter for attention to artificial openingsZ43
- Encounter for fitting and adjustment of external prosthetic deviceZ44
- Encounter for adjustment and management of implanted deviceZ45
- Encounter for fitting and adjustment of other devicesZ46
- Orthopedic aftercareZ47
49 more in this chapter.