How do I resolve a CO-133 denial?

Pull the original claim and review the denial reason and any RARC codes Research the payer's policy for CARC 133 to understand the basis for denial See full resolution steps at tryarceum.com.

Can I appeal a CO-133 denial?

CO-133 denials are generally not appealable. This is a pending status code, not a denial, so there is nothing to appeal until the payer completes their review and issues a final decision.

CARC Code

133

🟡 Soft Denial

Service Line Pending Further Review

The insurance company needs more time to review this specific service before making a payment decision. This is a temporary status that will be updated once the review is complete.

contractual

Resolution: 82%Medium difficulty7-14 days avg

How to resolve this denial

Which payer denied this claim?

Submit the related claim disposition (CRF or UB-04) with this claim

1
Pull the original claim and review the denial reason and any RARC codes
2
Research the payer's policy for CARC 133 to understand the basis for denial
3
Gather supporting documentation addressing the denial reason
4
Submit a formal appeal with the documentation within the plan's appeal window
5
Follow up on the appeal within 30 days and document all communication

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-133 — stats, related codes, appeal template

82%

Recovery Rate

7-14 days

Avg. Resolution

Medium

Difficulty

Rare

Frequency

Payer-Specific Notes

How major payers handle CARC 133 by specialty.

UnitedHealthcare

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

Common 835 Combinations

CARC 133 most often appears with these Group Code + RARC combinations on 835 remittances.

COCO-133This code indicates the payer has placed the service line in pending status and

Look up any combination →

Appeal Letter Template

Generic appeal template for CARC 133 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 133 indicating: "The disposition of the related claim has not been 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.

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