How do I fix OHIP error code AO3?

Check who was the MRP on the service date and what MRP visits were already paid for this admission. If you weren't the MRP, or the MRP visit was already paid, bill the regular subsequent visit code for your specialty instead (for example C002 in family practice). If a date is wrong, correct it. Resubmit the corrected claim within three months of the service date if you can. If that window has passed but the claim was first submitted on time, use the Ministry's stale-dated resubmission process: one stale-dated claim file through MCEDT, then an email to ClaimsManagement@ontario.ca with the Error Reports showing the original submission date.

When shouldn't I resubmit a AO3 claim?

Another physician was MRP for most of that day and you are billing the same MRP visit again.

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Error code

AO3 — Most Responsible Physician (MRP) Visit Already Paid

Q: What does OHIP error code AO3 mean?

AO3 means an MRP visit for this hospital stay was already paid. If you weren't the MRP on that day, bill a regular subsequent visit.

MRP visit already paid

A Most Responsible Physician visit, such as C122 or C123, was already paid for this patient's hospital stay.

What to do: If you weren't the MRP that day, or it was already paid, bill the regular subsequent visit code, such as C002.

Code: AO3
Description: Most Responsible Physician (MRP) Visit Already Paid

Explanation

Updated October 26, 2026

AO3 means an MRP visit for this hospital stay was already paid. If you weren't the MRP on that day, bill a regular subsequent visit.

What it means

AO3 means OHIP rejected a Most Responsible Physician (MRP) visit because one has already been paid for this patient's hospital stay.

C122 (day after the admission assessment) and C123 (second day) are limited to one each per admission. Only one of C122 or C142, and one of C123 or C143, is payable per admission. C122 and C123 aren't payable on the same day as discharge visits C124 or C126. If the patient is transferred within the hospital on one of those days, only the physician who was MRP for most of that day can claim it. Physicians who aren't the MRP may be paid a lesser visit fee (GP44).

Common causes

Two physicians both billed the MRP visit for the same day
C122 or C123 billed twice in one admission, or with C142 or C143
C122 or C123 billed on the day of discharge
A wrong service or admission date

How to fix it

Check who was the MRP on the service date and what MRP visits were already paid for this admission.
If you weren't the MRP, or the MRP visit was already paid, bill the regular subsequent visit code for your specialty instead (for example C002 in family practice).
If a date is wrong, correct it.
Resubmit the corrected claim within three months of the service date if you can. If that window has passed but the claim was first submitted on time, use the Ministry's stale-dated resubmission process: one stale-dated claim file through MCEDT, then an email to [email protected] with the Error Reports showing the original submission date.

Don't resubmit if

Another physician was MRP for most of that day and you are billing the same MRP visit again.

How APEX handles it

APEX reads your error reports and remittance advice from MCEDT and lists claims rejected with this code in its Correction Centre for you to correct and resubmit. See how APEX works · Pricing

Related codes: HB, SV, SF, SW