CPT code 90483 describes immunization counseling provided to a patient or caregiver when the provider does not administer the discussed vaccines on the same date of service; the service covers face-to-face counseling lasting greater than 10 minutes up to 20 minutes. Service type: preventive/educational counseling; typical site of service: office or outpatient clinic visit where vaccine discussion occurs but administration is deferred. This code is used to document and bill the timed counseling encounter focused on vaccine information, risks, benefits, and decision-making.