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Denial codes
These are the codes a payer puts on a denied claim. Look one up to learn what it means and the usual fix. This is general information, not advice on a specific claim.
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All codes in this library
- CO-4: The service code and the extra code that adds detail to it do not match.
- CO-11: The health reason given does not fit the service billed.
- CO-16: Something is missing from the claim, or a part of it was filled in wrong.
- CO-18: The payer already has this exact claim or service line.
- CO-22: Another payer may have to pay first.
- CO-29: The claim was sent after the payer's last date for it.
- CO-31: The payer cannot match the person on the claim to a person it covers.
- CO-45: The charge is more than the most the payer will allow for that service.
- CO-50: The payer says this service is not needed for this person's health in this case.
- CO-96: The payer does not cover this charge.
- CO-97: The payer already paid for this service as part of another service.
- CO-109: This payer does not cover this claim. Another payer may.
- CO-140: The member number and the name on the claim do not match.
- CO-146: The health reason was not valid on the date the service was given.
- CO-181: The service code was not valid on the date the service was given.
- CO-197: There is no approval on file for this service.
- CO-204: This service is not covered under this person's current plan.
- CO-226: The payer asked for more facts and did not get them, or got too little.
- CO-236: These two service codes do not go together on the same day under the payer's edit rules.
- CO-242: The service was not given by a provider in the payer's network, or not by the person's main provider.
- CO-252: The payer needs a paper or file attached before it can decide the claim.
- CO-272: The payer's rules for coverage were not met.
- OA-18: The payer already has this exact claim or service line.
- OA-23: An earlier payer's decision changed what this payer owes.
24 codes in this library. This is general information, not advice on a specific claim.
Learn on the job
Learn on the job with real denied claims.
Working denied claims is the medical claims desk's daily work. Read a code, find what is missing, fix the claim, or write the appeal.