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Billing code

G845A — Measles, Mumps, Rubella (MMR, Priorix)

MMR vaccine

Bill G845 for the measles, mumps and rubella vaccine; add G700 when it is the only reason for the visit.

Watch for: Bill varicella vaccine separately as G848, with only one G700 per patient per day.

Code

G845A

Description

Measles, Mumps, Rubella (MMR, Priorix)

FHO+ basket

Covered by the FHO+ base rate payment for enrolled patients, and shadow billed at 30% (50% for Schedule 2B procedures).

Effective date

Apr 1, 2026

Termination date

No end date

Explanation

Updated October 26, 2026

Immunization with the measles, mumps and rubella (MMR) vaccine. Add G700 when the vaccine is the only reason for the visit.

What it covers

G845 is the immunization code for the measles, mumps and rubella vaccine (MMR) (J54).

Varicella vaccine is billed separately as G848 (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: a Schedule 2B core service, so for enrolled patients shadow billing is 50% of the fee (Agreement p.59 §4.3–4.4, p.89).
• FHO: childhood immunizations count toward the annual childhood immunization bonus for enrolled patients aged 30–42 months (Agreement p.65 §8.1).

Often billed with

• G700 when vaccines (alone or with other (+) procedures) are the only reason for the visit (J3, J54).
• An assessment such as A007 (intermediate assessment or well baby care) when the vaccine is given at a regular visit; G700 isn't added then, because the vaccine isn't the sole reason (A4, J3).

Common rejections

• 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.
• 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.
• EQB: OHIP describes this as 'Solo billing number inactive on service date': the solo billing number on the claim wasn't active on the day of service.
• A3H: The line billed more services of this code than OHIP's fee schedule master allows; check the number of services and resubmit.
• VH8: The date of birth on the claim doesn't match OHIP's record for that health number; correct it and resubmit.

Related codes: G700, G848, G841, G846, G844, A007

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

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