CARC Code
164
Required Documentation Received Late
The insurance company requested additional documents (like medical records or a letter of medical necessity) to process the claim, but those documents were submitted after the deadline.
missing infoHow to resolve this denial
Submit missing documentation with appeal request within timely filing window
- 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
▶✓ 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-164 — stats, related codes, appeal template
82%
Recovery Rate
7-14 days
Avg. Resolution
Medium
Difficulty
Occasional
Frequency
Payer-Specific Notes
How major payers handle CARC 164 by specialty.
UnitedHealthcare
Review UHC's online claim status tool for additional detail on this adjustment.
Appeal Letter Template
Generic appeal template for CARC 164 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 164 indicating: "Attachment/other documentation was not received in a timely fashion.." 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.
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