CARC 31 Active

OA-31: Patient Cannot Be Identified as Insured

TL;DR

Adjustment in a COB or secondary payer context. Review the coordination of benefits details to determine the responsible party.

Action
Verify & Resubmit
Who Pays
Depends
Appeal
Yes
Patient Impact
Indirect
Disclaimer
This content is for informational purposes only and does not constitute professional billing advice. Always verify information against your payer contracts and current coding guidelines. Consult a certified billing specialist for specific claim issues.

What Does OA-31 Mean?

With OA (Other Adjustments), CARC 31 typically appears in a coordination of benefits (COB) context. Patient not found in secondary payer's enrollment records. The financial responsibility depends on the specific arrangement between payers — review the primary payer's EOB and the COB terms to determine the correct course of action.

CARC 31 indicates patient cannot be identified as insured. The payer determined that the service or a portion of it does not meet coverage criteria under the patient's current plan benefits or the applicable coverage rules.

Common scenarios that trigger this adjustment include: the member ID submitted on the claim does not match any active enrollee in the payer's system; Claim submitted to wrong insurance company - patient has coverage with a different carrier; Patient's name on the claim does not match the name on file with the payer (maiden vs married name, legal name change). The group code paired with CARC 31 determines who bears the financial responsibility — CO places it on the provider as a contractual obligation, OA indicates a coordination of benefits or other payer adjustment, PR shifts it to the patient.

Common Causes

Cause Frequency
Secondary payer cannot identify patient Patient not found in secondary payer's enrollment records Most Common

How to Resolve

  1. Review the coordination of benefits Examine the OA-31 adjustment to understand how it fits within the primary/secondary payer relationship or other multi-payer context.
  2. Verify primary payer adjudication Review the primary payer's EOB to understand the basis for the secondary payer's OA adjustment.
  3. Determine the responsible party Based on the COB review, identify whether the adjustment should be absorbed, billed to another payer, or if additional documentation is needed.
  4. Appeal or resubmit if needed Appeal with enrollment documentation and correct member demographics.
  5. Follow up Monitor the claim status and take additional action as needed based on the COB determination.
Appeal Guide

Appeal with enrollment documentation and correct member demographics.

Common RARC Pairings

The RARC code tells you exactly what triggered the OA-31:

RARC Description
N30 Patient not eligible Verify enrollment with secondary payer →

How to Prevent OA-31

Also Filed As

The same CARC 31 may appear with different Group Codes:

CO-31 PR-31

Related Denial Codes

OA-26 — Expenses Incurred Prior to Coverage OA-27 — Expenses Incurred After Coverage Terminated OA-32 — Patient Not Eligible Dependent OA-33 — Insured Has No Dependent Coverage OA-34 — No Coverage for Newborns

Sources

  1. https://x12.org/codes/claim-adjustment-reason-codes
  2. https://revenuecyclemgmt.com/claim-adjustment-reason-codes/
  3. https://www.rivethealth.com/blog/carcs-rarcs-claim-adjustment-remittance-advice-codes
  4. Codes maintained by X12. Visit x12.org for official definitions.