ICD-10 Code for Immunization

The ICD-10-CM 2027 alphabetic index lists immunization with the subterms below. More specific codes depend on the details documented, as listed in the official index (21 codes, 19 billable).

Index entries for Immunization

ABO – see Incompatibility, ABO
- in newborn – P55.1
appropriate for age
- child (over 28 days old) – Z00.129
  - with abnormal findings – Z00.121
complication – see Complications, vaccination
encounter for – Z23
not done (not carried out) – Z28.9 – see also Underimmunization status
- because (of)
  - acute illness of patient – Z28.01
  - allergy to vaccine (or component) – Z28.04
  - caregiver refusal – Z28.82
  - chronic illness of patient – Z28.02
  - contraindication NEC – Z28.09
  - delay in delivery of vaccine – Z28.83
  - group pressure – Z28.1
  - guardian refusal – Z28.82
  - immune compromised state of patient – Z28.03
  - lack of availability of vaccine – Z28.83
  - manufacturer delay of vaccine – Z28.83
  - parent refusal – Z28.82
  - patient's belief – Z28.1
  - patient had disease being vaccinated against – Z28.81
  - patient refusal – Z28.21
  - religious beliefs of patient – Z28.1
  - specified reason NEC – Z28.89
    - of patient – Z28.29
  - unavailability of vaccine – Z28.83
  - unspecified patient reason – Z28.20
partial – see also Underimmunization status
- for COVID-19 – Z28.311
Rh factor
- affecting management of pregnancy NEC – O36.09- (header)
  - anti-D antibody – O36.01- (header)
- from transfusion – see Complication(s), transfusion, incompatibility reaction, Rh (factor)

How to choose the right code

Start with the main term, then pick the indented subterm that matches the documentation (type, cause, site, laterality, episode of care). Always confirm the code in the tabular list: follow its Excludes1/Excludes2, “code first” and “use additional code” notes, and add a 7th character where required.

Source: CDC/NCHS ICD-10-CM FY2027 alphabetic index.