Question: I filed a claim, and it was rejected. When I reviewed the claim, I discovered the National Provider Identifier (NPI) number was incorrect and fixed the error. Should I now appeal the claim? AAPC Forum Subscriber Answer: You cannot appeal a claim that was never technically filed. Because of the error with the billing provider’s NPI, the payer rejected the claim. This is not the same as a denial. A claim rejection occurs before the claim is even processed, meaning it was never filed. You can only appeal once the payer denies the claim, meaning the payer tells you they won’t pay after accepting the filing. This may be due to terms of the patient-payer contract, incorrect procedure or diagnosis codes, or other reasons the payer notes during processing. When you receive a rejection, you need to fix the errors and resubmit the claim with the corrected information. This is not an appeal, as explained. If the claim is denied at that point, you can appeal if warranted.