Corrected claim

A corrected claim tells the payer to replace what it already has. Because the payer processed the original and assigned it a claim number, a plain resubmission would be rejected as a duplicate. Instead the claim carries the claim frequency code for a replacement, 7, in the 837P (the resubmission code field on a CMS-1500), plus the payer’s original claim number, so the payer can match the two and adjudicate the new version in place of the old. A separate frequency code voids a claim entirely.

Corrected claims are the fix for most data denials: a wrong or missing modifier, a unit count, a diagnosis pointer, a rendering NPI, a place of service, a date, or a missing authorization number that existed all along. They are not the fix for a coverage or medical necessity decision; that needs an appeal with records. Payers also apply a filing window to corrections, counted from the original remittance date or the original date of service depending on the payer, so a correction has to be filed as fast as an original.

The mistake is sending a brand new claim instead. Without the frequency code and the original number, the payer sees a duplicate and denies it, the biller sees a second denial, and two or three cycles pass before anyone notices the correction never landed. A smaller mistake is correcting only the denied line. Check how the payer treats a replacement: many replace the whole claim, so the paid lines have to be on it too.