Getting claims paid, and what to do when they are not.
Most practices believe they can prove when a claim was filed. Then a CO-29 arrives, they pull the file, and the document they kept turns out to prove something else. A 999 acknowledgment confirms your clearinghouse received your file. Only a 277CA confirms the payer received your claim, and only the second one wins an appeal. Plus why a rejected claim never stopped the clock.
CO-97 means the payer decided one of your codes was already paid for inside another. Before writing an appeal, look up the modifier indicator on that code pair. If it is 0, no modifier and no documentation will ever unbundle it, and repeated override attempts are exactly the pattern audit selection looks for. Here is how to tell an appealable denial from a correct one in under a minute.
Most billers read a remittance from the top down and post what they see. That works until the deposit does not match what the remittance said you were paid. When that happens the money is almost always in a segment near the bottom that nobody reads. Here is where provider level adjustments hide, why forward balances are so hard to trace, and a ten minute reconciliation that catches them.
CO-45 means your billed charge exceeded the allowed amount, and the difference is a contractual write-off. It is almost never an error and rarely worth appealing. What matters is what you do with the difference, because billing the patient for it is balance billing. Here is how to tell a normal write-off from a genuine underpayment.