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Billing code

G590A — Influenza

Flu shot

Bill G590 for an injected influenza vaccine; add G700, or Q590A for FHO and FHN physicians, when it is the only reason.

Watch for: Don't add G700 or Q590A when you also bill an assessment for the visit.

Code

G590A

Description

Influenza

FHO+ basket

Not in the FHO+ base rate basket (Schedule 2 or 2B).

Effective date

Apr 1, 2026

Termination date

No end date

Explanation

Updated October 26, 2026

Influenza vaccine given by injection. Add G700, or Q590A for FHO/FHN physicians, when the flu shot is the only reason for the visit.

What it covers

G590 is the immunization code for an influenza agent (J54). Intranasal influenza vaccine has its own code, G592 (J54).

Billing rules

• Marked (+): when the immunization is the sole reason for the visit, add G700, once per patient per day however many vaccines or (+) procedures are given (J3, J54).
• G700 is not payable in hospital, and is paid at 15% of its fee for patients enrolled to a capitation-based group (J3).
• May be delegated to trained office staff, even when you aren't on site, for your own patient; the chart must name who gave it (GP62–GP63).
• Payable on the same day as a counselling service by the same physician (GP58).
• The Schedule notes an immunization may be uninsured in some circumstances and refers to section 24 of Regulation 552 under the Health Insurance Act (J54, AA1).
• FHO and FHN physicians bill Q590A instead of G700 when the flu shot is the sole reason for the visit, for enrolled and non-enrolled patients (Agreement p.72 §11.7; Appendix Q AQ3, information only).
• Q590A is not payable with G700, and not with an assessment: bill the assessment and G590 instead (OMA Q-codes p.14).
• Only one of Q590A or Q593A is payable per patient per year (Agreement p.72 §11.7–11.8).
• FHO: the influenza bonus counts enrolled patients 65 and over vaccinated for the season by January 31 (Agreement p.65 §8.1).

Often billed with

• G700 when the flu shot is the only reason for the visit (J3, J54), or Q590A instead for FHO/FHN physicians (Agreement p.72 §11.7).
• An assessment, with no G700 or Q590A, when the flu shot is given during a regular visit (J3; OMA Q-codes p.14).

Common rejections

• VJ7: OHIP received the claim more than three months after the service date, so it was rejected as stale-dated (GP9).
• EH2: The health card version code on the claim doesn't match OHIP's record, often because the patient has a newer card; get the current version code and resubmit.
• A1A: OHIP describes this as 'Outside Service Period': the service date falls outside the period in which OHIP accepts the code; check the service date.
• EH4: OHIP's record shows the patient's coverage ended before the service date; confirm the health number and service date, then the patient's coverage.
• A3H: The line billed more services of this code than OHIP's fee schedule master allows; check the number of services and resubmit.

Related codes: G700, G592, G593, G538, Q590

Source: Schedule of Benefits (July 1, 2026), Diagnostic and Therapeutic Procedures, Injections or Infusions — Immunization, page J54

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