Accurate CPT coding is the backbone of clean claims, timely reimbursement, and compliance in medical billing. One of the most commonly used codes in vaccine administration is CPT 90471. If billed or documented incorrectly, it can trigger denials, payer audits, and delayed payments.
This guide explains what CPT 90471 covers, when to use it, how it differs from related codes, and the key documentation requirements based on the latest AMA and CMS guidelines.
What Is CPT Code 90471?
CPT 90471 is defined by the AMA as:
“Immunization administration (percutaneous, intradermal, subcutaneous, or intramuscular injections); one vaccine (single or combination vaccine/toxoid), per day.”
👉 Key points:
- Covers administration only, not the vaccine itself.
- Applies to the first injected vaccine given during a patient encounter.
- If additional vaccines are given during the same visit, use CPT 90472 for each additional injection.
When to Use CPT 90471
Use 90471 when:
- Administering a single injected vaccine at a visit (flu, tetanus, hepatitis A, rabies, etc.).
- Billing for the first injection in a multi-vaccine visit.
Example Scenarios
- Flu shot (IM injection) at an annual wellness visit → 90471
- Tetanus vaccine after a wound injury → 90471
- Hepatitis A vaccine given at a travel clinic → 90471
When NOT to Use CPT 90471
- Additional injected vaccines during the same visit → bill 90472
- Oral or intranasal vaccines (e.g., FluMist, rotavirus) → bill 90473
- COVID-19 vaccines → use AMA-issued product-specific codes (91300-91320, etc.) + administration codes (0001A-0044A).
CPT 90471 vs Related Codes
| Code | Description | When Used |
|---|---|---|
| 90471 | First injected vaccine (IM, SC, ID, percutaneous) | First shot of the visit |
| 90472 | Each additional injected vaccine (add-on) | Second, third, etc. |
| 90473 | First oral/intranasal vaccine | First FluMist, rotavirus |
| 90474 | Each additional oral/intranasal vaccine (add-on) | If more than one |
ICD-10 Codes Commonly Used with 90471
To avoid claim denials, pair 90471 with an appropriate diagnosis code:
- Z23 – Encounter for immunization (most common)
- W54.0XXA – Dog bite, initial encounter (rabies vaccine)
- S01.409A – Open wound, initial encounter (tetanus vaccine)
- Z00.129 – Routine child health checkup with vaccines
👉 Always link Z23 when the encounter is primarily for immunization. Use additional codes when vaccines are tied to specific injuries or exposures.
Documentation Requirements (Per CMS & AMA)
For clean claims and audit protection, every vaccine encounter billed under 90471 must include:
- Vaccine details: name, manufacturer, lot number, expiration date, dose.
- Route and site: e.g., “0.5 mL IM, left deltoid.”
- Patient identification & consent: signed or electronic consent.
- Diagnosis code: usually Z23.
- Provider signature: electronic or written authentication.
- Observation notes: record tolerance or side effects.
Modifiers That May Apply
- Modifier 25 – If a significant and separately identifiable E/M service is performed on the same day as the vaccine.
- Modifier 59 – Rare, but may apply if distinct procedural services are provided (e.g., multiple same-day vaccine administrations in separate anatomic sites).
Common Billing Errors to Avoid
- Using 90471 for additional vaccines instead of 90472.
- Forgetting to bill the vaccine product code along with administration.
- Missing Z23 or other diagnosis codes.
- Leaving out lot number, expiration date, or injection site in documentation.
Reimbursement Notes
- Most commercial payers and Medicaid cover vaccine administration under preventive care.
- Medicare Part B covers certain vaccines (flu, pneumococcal, COVID-19). Others (Tdap, shingles, hepatitis) may fall under Part D.
- Reimbursement amounts vary by payer and state Medicaid policies.
Quick Takeaways
- 90471 = first injected vaccine of the visit.
- 90472 = each additional injected vaccine.
- 90473/90474 = oral/nasal vaccines.
- Always pair with Z23 (and additional ICD-10 codes if appropriate).
- Detailed documentation = fewer denials and faster reimbursement.