Denial code

CO 45

Charge is above the contracted rate. The difference is written off.

Not a denial CO

What CO 45 means

CO — Contractual obligation — the provider absorbs it and cannot bill the patient.

So the balance cannot move to the patient. Either the appeal recovers it or the practice absorbs it. That makes the appeal decision the whole decision on this line.

Is it worth appealing?

Not a denial. A contracted write-down or patient responsibility. Not money you lost.

Why it fires

In the order we see it.

  1. The charge exceeds the contracted rate. This is the write-down you agreed to.

What to do

Contractual adjustment. Only worth review if the fee schedule loaded wrong.

What actually wins it

The documentation, not the argument.

Your contracted fee schedule, if the allowed amount looks wrong for the code.

The common mistake. Do not appeal a correct contractual adjustment. Do check that the fee schedule loaded correctly, because a bad load shows up here first.

Where this comes from. This is our own reading of the code, not the payer's and not a copy of the standards text. We classify it from how these denials actually resolve. Where we are unsure, we say so rather than guessing.

Related codes

Free denial review

How much of this is sitting in your write-off pile?

Send your denial summary for the last ninety days. Four columns: payer, CARC code, count, billed amount. I will tell you which were winnable and what they were worth.

Send your denial summary No patient data. No BAA. No charge.