AGAR Guide
CARC18ReferenceCurrentVerified Aug 15, 2026

CARC 18

AR Guide Workflow

Duplicate Claims

The payer identified the claim as a duplicate of a previously processed claim. Verify the original before doing anything — this is often a no-action item.

Open denial workflow

AR Guide explanation

What it means

The payer identified the claim as an exact duplicate of a claim/service already processed.

AR Guide knowledge

Common denial category

Duplicate Claims — The payer identified the claim as a duplicate of a previously processed claim. Verify the original before doing anything — this is often a no-action item.

AR Guide knowledge

Common causes

  • Same claim submitted twice
  • Corrected claim sent as a new claim instead of a replacement
  • Duplicate line items on one claim

AR Guide knowledge

What AR should verify

  1. Search for the prior claim using the same dates of service and charges
  2. Confirm whether the original claim was already paid
  3. Check if this was meant to be a corrected/replacement claim

AR Guide knowledge

Recommended action

  1. If it is truly a duplicate, no appeal is needed — confirm the original was handled correctly
  2. If it is a corrected claim, resubmit with the correct replacement indicator

AR Guide knowledge

QA checkpoint

  • Use a claim scrubber that detects duplicates before submission
  • Train staff on replacement vs. new claim submission

About this guidance: Note

AR Guide knowledge is general reference content written by our team — it is not payer-specific policy and never replaces the payer’s documentation or your contract. Always confirm specifics with the payer.