Denials List
Denials List
Use this list as a quick denial-code reference. Search by denial code, description, or related billing keywords such as modifier, authorization, timely filing, duplicate, or medical necessity.
Search checks code, description, and hidden keywords. Click any code to open its detail page.
| Code | Description |
|---|---|
| CO-04 | The procedure code is inconsistent with the modifier used or a required modifier is missing. |
| CO-05 | The procedure code or bill type is inconsistent with the place of service. |
| CO-06 | The procedure or revenue code is inconsistent with the patient age. |
| CO-07 | The procedure code is inconsistent with the patient gender. |
| CO-08 | The procedure code is inconsistent with the provider type or specialty. |
| CO-11 | The diagnosis is inconsistent with the procedure billed. |
| CO-16 | Claim or service lacks required information or contains a billing/submission error. |
| CO-18 | Duplicate claim or duplicate service. |
| CO-29 | The time limit for filing the claim has expired. |
| CO-45 | Charge exceeds fee schedule, maximum allowable, contracted, or legislated fee arrangement. |
| CO-50 | The service was denied because payer considers it not medically necessary. |
| CO-96 | Non-covered charge or service under the patient plan. |
| CO-109 | Claim or service is not covered by this payer or contractor. |
| CO-151 | Payer information does not support the frequency or level of service billed. |
| CO-197 | Precertification, authorization, notification, or referral was absent. |
No matching denial code found. Try another keyword or code.
How to use this denial list
Start with the denial code from the EOB, ERA, clearinghouse rejection, or payer portal. If you do not know the code, search by the problem such as missing modifier, wrong payer, authorization, or timely filing.
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