OA-23 Denial Code: Prior Payer Adjudication, Explained

OA-23 is not a denial. It shows up on secondary claims and represents the impact of what the primary payer already paid or adjusted. The secondary payer is telling you that amount is accounted for. What matters is the patient responsibility left after both payers.

1. What OA-23 means

OA (Other Adjustment): neither a contractual write-off nor patient responsibility.
23: the impact of prior payer(s) adjudication, including payments and adjustments.

The secondary payer uses OA-23 to show the portion of the charge it did not consider because the primary payer already handled it.

2. How to read OA-23 on a secondary claim

Line on the secondary remittance	Example
Billed charge	$200
OA-23 (impact of the primary payer's payment and adjustments)	$170
Secondary payer paid	$25
PR (patient responsibility left)	$5

Post the secondary payment and the remaining PR amount. The OA-23 amount is not a write-off you choose to take and not something to bill anyone for. It reflects the primary payer's processing.

3. When the secondary pays nothing

A secondary payment of $0 with OA-23 often means the primary payer already paid as much as or more than the secondary would have allowed. Depending on the secondary plan's coordination method, it pays only up to its own allowed amount, minus what the primary paid. That can be correct.

4. When OA-23 points to a problem

The primary payment information sent was wrong or incomplete, so the secondary calculated from bad numbers. Send a corrected claim with the right primary remittance data.
The primary was billed incorrectly, for example the wrong plan was treated as primary. See CO-22.
The primary later reprocessed the claim. The secondary needs to be rebilled with the updated amounts.

Related: PR-1, CO-45, and the full CARC and RARC codes list.

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Frequently asked questions

What does OA-23 mean?

OA-23 means the impact of prior payer adjudication. It appears on secondary claims and represents what the primary payer already paid or adjusted. It is not a denial.

Is OA-23 a write-off?

Not in the usual sense. It reflects the primary payer's processing. Post the secondary payment and any remaining patient responsibility.

Why did the secondary insurance pay zero with OA-23?

Often because the primary payer already paid as much as or more than the secondary would allow under its coordination method. Check that the primary payment information sent to the secondary was correct.

Can I bill the patient for an OA-23 amount?

No. Only the PR amounts on the remittance are patient responsibility.

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OA-23 Denial Code: What It Means on Secondary Claims