Official CARC description: “This care may be covered by another payer per coordination of benefits.” Here’s what it actually means, why it fires, and how to get the claim paid.
The payer believes someone else should pay first — their COB file says the patient has other primary coverage (spouse's plan, Medicare, auto or work-comp carrier). Until the COB record is straightened out, every claim will bounce.
Liability group: CO = Contractual Obligation — the provider absorbs it — the amount cannot be billed to the patient. If the denial is wrong, the money is recovered by correcting or appealing the claim, not by balance-billing.
Ask the patient to update COB with the payer (usually a 10-minute phone call — give them the number)
Verify actual primacy: employment status, accident involvement, Medicare entitlement
Bill the true primary; then resubmit here with the primary EOB attached
If there is genuinely no other coverage: get the payer to note it and reprocess
Appealable once the facts are documented: submit the updated COB confirmation or the primary payer's EOB (or denial) and request reprocessing. The killer is speed — COB denials age into timely-filing losses.
Fill in the denial facts — use placeholders, never real patient data (the letter keeps [PATIENT NAME]-style fields so you can merge real details privately). A payer-ready draft with an enclosure checklist comes back in ~20 seconds.
Your appeal letter draft will appear here.
This care may be covered by another payer per coordination of benefits. In practice: The payer believes someone else should pay first — their COB file says the patient has other primary coverage (spouse's plan, Medicare, auto or work-comp carrier). Until the COB record is straightened out, every claim will bounce.
CO stands for Contractual Obligation — the provider absorbs it — the amount cannot be billed to the patient. If the denial is wrong, the money is recovered by correcting or appealing the claim, not by balance-billing.
Appealable once the facts are documented: submit the updated COB confirmation or the primary payer's EOB (or denial) and request reprocessing. The killer is speed — COB denials age into timely-filing losses.