CARC 18: Duplicate claim/service
Your insurer flagged this claim as a duplicate of one already processed.
What this means for your claim
The same service appears to have been billed twice. This may be a billing error, or it may be a legitimate separate encounter that needs distinguishing information.
What to do next
- 1
Ask your provider for the original claim number and the date of the first submission.
- 2
If this is a genuinely separate service, ask the provider to resubmit with a different date of service, modifier, or claim note clarifying the distinction.
- 3
If it truly was a duplicate submission error, no action is needed beyond confirming the original was paid correctly.
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