# CARC 22 Denial Code (Care May Be Covered by Another Payer (Coordination of Benefits)) | ANSI 835 EDI Spec
> Comprehensive healthcare EDI technical reference and denial resolution guide for Claim Adjustment Reason Code 22 (Care May Be Covered by Another Payer (Coordination of Benefits)) under ANSI ASC X12 835 005010X221A1.

- **Canonical URL:** https://stanzaapi.com/tools/x12-parser/carc/carc-22-coordination-of-benefits
- **Governing Standard:** ANSI ASC X12 Standards (005010) (Accredited Standards Committee X12 / HIPAA 5010)
- **Edge Latency SLA:** <2ms Edge (Cloudflare V8 Isolates)
- **Execution Model:** Pure compute $f(x) = y$, 100% In-Memory (Zero Store, Zero Log)

## Technical Overview & Governing Rules
Claim Adjustment Reason Code (CARC) 22 communicates: "This care may be covered by another payer per coordination of benefits.".

In ANSI X12 835 Electronic Remittance Advice (ERA) files, CARC 22 is reported in Loop 2110 (Service Payment Information) or Loop 2100 (Claim Payment Information) under the Claim Adjustment (CAS) segment with Group Code 'OA' (Other Adjustment), formatted as: CAS*OA*22*AMOUNT~.

Root Cause: Payer records indicate another insurer is primary (e.g., commercial employer plan primary over Medicare, or auto/workers comp coverage).

Adjudication & Appeal Strategy: Submit claim to the designated primary payer first; upon receiving the primary 835 ERA, bill the secondary payer with primary payment details in Loop 2320 (COB).

## Specification Matrix
| Attribute | Value | Technical Guidance |
| --- | --- | --- |
| Reason Code | CARC 22 | Care May Be Covered by Another Payer (Coordination of Benefits) |
| Standard Group Code | OA | Other Adjustment |
| ANSI 835 Segment | CAS*OA*22*AMOUNT~ | Loop 2110 or Loop 2100 |
| Balance Billing Patient | Prohibited until secondary coordination is complete. | Compliance with billing regulations |
| Common RARCs | N517, MA04 | Remittance Advice Remark Codes |
| Recommended Action | Submit claim to the designated primary payer first; upon receiving the primary 835 ERA, bill the secondary payer with primary payment details in Loop 2320 (COB). | Workflow for billing teams |

## Standard JSON Response Model
```json
{
  "transactionType": "835",
  "claimNumber": "CLM-2026-001",
  "adjudication": {
    "billedAmount": 500,
    "paidAmount": 0,
    "adjustments": [
      {
        "groupCode": "OA",
        "groupName": "Other Adjustment",
        "reasonCode": "22",
        "reasonDescription": "Care May Be Covered by Another Payer (Coordination of Benefits)",
        "adjustmentAmount": 500
      }
    ]
  }
}
```

## Frequently Asked Questions & Edge Cases
### Q: What does CARC 22 mean on an 835 ERA?
**A:** CARC 22 signifies: "This care may be covered by another payer per coordination of benefits.". It explains why the payer did not pay the full billed charge.

### Q: Can a provider balance-bill the patient for CARC 22?
**A:** Prohibited until secondary coordination is complete.

### Q: How do medical billing teams resolve and appeal CARC 22?
**A:** Submit claim to the designated primary payer first; upon receiving the primary 835 ERA, bill the secondary payer with primary payment details in Loop 2320 (COB).