How do I fix OHIP error code 55?

Find the original claim: same patient, service date and fee code. Look for a 57 line for the same service on the same RA. If the 55 and 57 together leave the amount you expected, there is nothing to do. Check the RA messages and recent INFOBulletins. Large reprocessing runs are usually announced. If the net result is lower than you believe is correct, send a Remittance Advice Inquiry (RAI) through eSubmit, or on form 0918-84, within 7 months of the date of the RA that shows the deduction. Explain why the original payment should stand.

When shouldn't I resubmit a 55 claim?

Never send a 55 line as a new claim. It is an adjustment, not a rejection. The 55 is offset by a matching 57. The deduction follows a roster change or Ministry reprocessing that you agree with.

< Error codes

Error code

55 — Deduction to adjust an earlier claim

Q: What does OHIP error code 55 mean?

OHIP took back money paid on an earlier claim, usually because it reprocessed that claim. Check it against its matching 57 line first.

Payment taken back

OHIP reversed all or part of a payment on an earlier claim, usually because it reprocessed that claim.

What to do: Look for the matching 57 line on the same remittance advice; if together they equal what you expected, nothing to do.

Code: 55
Description: Deduction to adjust an earlier claim

Explanation

Updated October 26, 2026

OHIP took back money paid on an earlier claim, usually because it reprocessed that claim. Check it against its matching 57 line first.

What it means

Code 55 marks a deduction. OHIP is reversing all or part of a payment it made on an earlier claim, so the line normally shows a negative amount on this month's Remittance Advice (RA). It is an accounting entry, not a new rejection.

Most 55 lines are half of a pair. When the Ministry reprocesses claims, it reverses the original payment with a 55 line and pays the reprocessed amount with a 57 line. If the payment didn't change, the two lines cancel out to $0. Ministry bulletins on mass adjustments, such as the 2025 paediatric age premium correction, describe this and say no action is needed.

A 55 with no matching 57, or a 57 for less, means OHIP has lowered what it pays for the earlier service. Roster changes are a common trigger: when a patient's enrolment changes, earlier visits can be reprocessed so they pay under the right arrangement.

Common causes

Ministry reprocessing after a fee or payment rule change (often a 55/57 pair that nets to $0)
A change in the patient's roster status after the visit
The outcome of a Remittance Advice Inquiry or claim correction
OHIP recovering a payment it considers made in error

How to fix it

Find the original claim: same patient, service date and fee code.
Look for a 57 line for the same service on the same RA. If the 55 and 57 together leave the amount you expected, there is nothing to do.
Check the RA messages and recent INFOBulletins. Large reprocessing runs are usually announced.
If the net result is lower than you believe is correct, send a Remittance Advice Inquiry (RAI) through eSubmit, or on form 0918-84, within 7 months of the date of the RA that shows the deduction. Explain why the original payment should stand.

Don't resubmit if

Never send a 55 line as a new claim. It is an adjustment, not a rejection.
The 55 is offset by a matching 57.
The deduction follows a roster change or Ministry reprocessing that you agree with.

How APEX handles it

APEX treats 55 as a code that can't be corrected and keeps it out of the Correction Centre. In claim history it pairs each 55 with the earlier payment it reverses and strikes both through, so the payment still standing for each fee code is easy to see; negative 55 lines are labelled Adjustment. See how APEX works · Pricing

Related codes: 57, I2, 35