CARC · CO group
CO-18
Exact duplicate claim or service
Contractual obligation; provider write-off unless appealed
- What it means
- The payer believes this claim or line was already submitted.
- Likely cause
- A biller resubmitted instead of sending a corrected claim, or two clearinghouse submissions went out for the same date of service.
- How to fix it
- Check whether the original paid. If it did, no action. If it denied, submit a corrected claim with the proper frequency code instead of a fresh claim.
- Revenue impact
- Often a false negative that hides a real unpaid claim underneath.
- duplicate
- process
Related codes
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