18Denial Code (CARC)Active
Denial Code OA 18: Duplicate Claim Resolution
Code 18 indicates that the claim was identified as an exact duplicate of a previously submitted claim for the same service. This typically means the payer has already processed an identical claim.
Who Pays: Group Code Liability
With group code OA, the provider cannot bill the patient for this adjustment. If state workers' compensation regulations require CO, then it is considered a contractual write-off and still not billable to the patient.
Why Claims Get Code 18
- A claim was submitted multiple times without any changes.
- The claim was resubmitted before the payer completed processing the original submission.
- A system error or batch processing issue caused duplicate submissions.
- Provider mistakenly resubmitted a claim due to a perceived non-response.
- Incorrect claim number or patient information led to confusion as a duplicate.
How to Fix & Resubmit
- Verify that the claim is indeed a duplicate by checking submission records.
- Ensure the original claim is still in process or has been processed correctly.
- Contact the payer if the original claim appears unpaid or unresolved.
- Correct any errors that led to the duplicate submission before resubmitting.
- If applicable, consult state workers' compensation guidelines for CO group code usage.
Corrected Claim or Appeal?
For code 18, submitting a corrected claim is not applicable as the issue is a duplicate submission. An appeal is unnecessary unless the original claim was denied incorrectly.
Preventing Future 18 Denials
- Track claim submissions to avoid resubmitting claims already sent.
- Implement a system to check claim status before resubmitting.
- Provide staff training on recognizing and preventing duplicate submissions.
- Use claim tracking software to monitor submission history and avoid duplicates.