How do I resolve a CO-163 denial?

Review the RARC code to identify the specific document(s) required Gather the required documentation from the provider or medical records department See full resolution steps at tryarceum.com.

Can I appeal a CO-163 denial?

Yes. Most CO-163 denials can be appealed within 60-180 days depending on payer. This is appealable if you can demonstrate the documentation was previously sent or can now provide the missing materials with proof of timely filing. Use our free tool to generate an appeal letter.

CARC Code

163

🟡 Soft Denial

Missing Attachment or Documentation

The claim mentioned that supporting documents or attachments would be included, but the payer never received them. The claim cannot be processed without this missing documentation.

missing info

Resolution: 82%Medium difficulty7-14 days avg

How to resolve this denial

Which payer denied this claim?

Resubmit claim with all required attachments and documentation

1
Review the RARC code to identify the specific document(s) required
2
Gather the required documentation from the provider or medical records department
3
Submit the documentation through the payer's electronic attachment portal or fax
4
Resubmit the claim with the attachment reference number if required
5
Confirm receipt and track to adjudication

Resolve this denial →

▶✓ Pre-action checklist — verify before contacting the payer

Review the full remittance advice (ERA/EOB) for additional RARC codes that explain the denial.
Verify the claim was submitted with correct patient eligibility and benefit information.
Check if this denial applies to a specific line item or the entire claim.

▶More about CO-163 — stats, related codes, appeal template

82%

Recovery Rate

7-14 days

Avg. Resolution

Medium

Difficulty

Common

Frequency

Payer-Specific Notes

How major payers handle CARC 163 by specialty.

UnitedHealthcare

Review UHC's online claim status tool for additional detail on this adjustment.

Common 835 Combinations

CARC 163 most often appears with these Group Code + RARC combinations on 835 remittances.

COCO-163The payer did not receive documentation that was referenced or requested withAppealable COCO-163+N433The claim was denied because referenced attachments or documentation were not

Look up any combination →

Appeal Letter Template

Generic appeal template for CARC 163 denials.

We are submitting a formal appeal for claim [CLAIM_NUMBER] for patient [PATIENT_NAME], date of service [DOS]. This claim was denied/adjusted with CARC 163 indicating: "Attachment/other documentation referred to on claim was not received.." We have reviewed the claim and are providing the attached documentation to support reconsideration. [SUPPORTING_DOCUMENTATION]. Please reconsider payment per the terms of our contract.

Generate a personalized appeal letter →

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