CO23 denial code description and corrective action

Impact of prior payer including payments and adjustments.

This denial mostly comes from the secondary insurance.
This denial occurs when the primary insurance payment is equal to or greater than the secondary insurance’s allowed amount. Let’s understand this with example.
Let us consider an example where the primary insurance allows $50, pays $40, and leaves $10 as coinsurance. The secondary insurance also allows $50, so it pays the remaining $10 coinsurance.
If the secondary insurance allows $45, then it will pay $5 and adjust the remaining $5 with code CO23.
If the secondary insurance allows $40 or less, then it will not pay anything and will adjust the full $10 coinsurance amount with code CO23.

First, we need to verify the status of the claim. This can be done by checking the status through the insurance web portal or by calling the payer.
Check if the secondary allowed amount is equal to the sum of the primary payment and the secondary payment. If yes, then the amount adjusted with CO23 should be written off.
If the secondary allowed amount is more than the sum of the primary and secondary paid amounts, then contact the insurance company and request the representative to reprocess the claim. Be sure to note the claim number, processed date, call reference number, and representative’s name, and then follow up on the claim after the provided TAT.
If the denial comes from the primary insurance, we must call the insurance company to find out the exact reason for the denial since there is no other prior payer. Discuss the details with the representative and then proceed accordingly.