CO-23Contractual ObligationCoordination of Benefits
CO-23 Denial Code: Impact of prior payer adjudication
The impact of prior payer(s) adjudication, including payments and/or adjustments, exceeds or affects this payer's liability.
Why CO-23 happens
- ●Secondary claim where primary payment plus adjustments meet or exceed the allowed amount
- ●Incorrect primary payment data on the secondary claim
How to fix a CO-23 denial
- 1
Verify the primary EOB amounts were reported correctly on the secondary claim
- 2
Confirm the secondary allowed amount — often no additional payment is due
- 3
Correct and resubmit if primary adjudication data was wrong
How to prevent it
Automate primary-to-secondary crossover data mapping to avoid keying errors.
Drowning in CO-23 denials?
OakClaim works every denial within 48 hours and builds prevention rules so they stop recurring.