Why did my insurance deny this claim?
Every line on an Explanation of Benefits carries a reason code. Here's what the 12 most common ones actually mean, whether you really owe the money, and the angle that wins an appeal.
- CO-45Charge exceeds fee schedule / contracted amountprovider
The provider billed more than their contract with the insurer allows. You are not responsible for the difference on in-network care.
- CO-97Charge is bundled — payment included in another serviceinsurer or provider
The insurer says this line item is already paid for as part of another procedure on the same day. It should not be billed separately.
- CO-109Claim not covered by this payer / contractorinsurer
The insurer says this claim should have gone to a different payer. Common when coverage changed or coordination-of-benefits wasn't updated.
- CO-151Payment adjusted — information does not support this many servicesinsurer or provider
The insurer thinks the provider billed too many units of the same service. Often a coding error, not a coverage issue.
- CO-197Precertification / authorization absentinsurer
The insurer says prior authorization was required but wasn't obtained.
- PR-1Deductible amountinsurer
This is being applied to your annual deductible — normal cost-sharing, not a denial. Verify the deductible math is correct.
- PR-3Copayment amountinsurer
Your plan's fixed copay for this visit type.
- PR-96Non-covered chargeinsurer
The insurer says this service isn't covered under your plan.
- PR-204Service not covered under current planinsurer
Similar to PR-96 — the insurer says your current benefit plan doesn't include this service.
- CO-11Diagnosis inconsistent with the procedureprovider
The insurer says the diagnosis code doesn't justify the procedure billed. Almost always a coding error, not a real medical issue.
- CO-16Claim lacks information — cannot be processedprovider
The insurer needs more info from the provider before they can process the claim.
- CO-18Duplicate claim / serviceprovider
The insurer flagged this as a duplicate of a claim already processed.
Not sure which code applies?
Upload your EOB and itemized bill — BillCheck reads the codes, flags the errors, and drafts the appeal letter for you.
Upload your billInformational tool — not legal, medical, or financial advice.