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G538
G538 – Other immunizing agents not listed above
OHIP Diagnostic & Therapeutic Procedures Code — DIAGNOSTIC AND THERAPEUTIC PROCEDURES · Schedule of Benefits
Provides for the administration of immunizing agents not otherwise listed in the Schedule. This fee is for the immunization procedure itself. Per the note on , if the immunization is the sole purpose of the patient visit, G700 should be added to the claim. This service is eligible to be delegated to a qualified office employee under the rules outlined in -.
When to Use
- Use G538 for the administration of non-standard immunizations not covered by specific codes, such as travel vaccines or specialized adult boosters.
- Use G538 when delegating the injection to a qualified office nurse or staff member under the supervision rules defined in GP62-GP63.
Common Pitfalls
- Billing G538 alongside W010 (Monthly Management of a Nursing Home patient) will result in an automatic rejection, as G538 is considered a component of the monthly management fee.
- Attempting to claim G700 when an assessment or consultation code (e.g., A007) is also billed for the same patient on the same day will lead to the rejection of the G700 premium.
- Submitting G538 for hospital-based immunizations is a common error; G700 is explicitly ineligible for payment when the procedure is performed in a hospital setting.
Billing Tips
- Always append G700 to your claim when the immunization is the sole reason for the visit to capture the additional $5.60 premium.
- If you are part of a capitation-based alternate funding plan, ensure your billing software correctly applies the 15% adjustment to the G700 premium as required by the Schedule.
Provider Fee$8.80
Effective: April 1, 2026
Category
J. Diagnostic and Therapeutic Procedures
Subcategory
DIAGNOSTIC AND THERAPEUTIC PROCEDURES
Service Type
Procedure
Code Classes
Diagnostic and Therapeutic Procedures
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