# CARC 197 Denial Code (Precertification / Prior Authorization Absent) | ANSI 835 EDI Spec
> Comprehensive healthcare EDI technical reference and denial resolution guide for Claim Adjustment Reason Code 197 (Precertification / Prior Authorization Absent) under ANSI ASC X12 835 005010X221A1.

- **Canonical URL:** https://stanzaapi.com/tools/x12-parser/carc/carc-197-prior-authorization-absent
- **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) 197 communicates: "Precertification/authorization/notification/prior determination absent, or exceeded.".

In ANSI X12 835 Electronic Remittance Advice (ERA) files, CARC 197 is reported in Loop 2110 (Service Payment Information) or Loop 2100 (Claim Payment Information) under the Claim Adjustment (CAS) segment with Group Code 'CO' (Contractual Obligation), formatted as: CAS*CO*197*AMOUNT~.

Root Cause: Procedure required mandatory payer prior authorization (PA) that was either not obtained before service or not included in Loop 2300 REF*G1 on the 837 claim.

Adjudication & Appeal Strategy: Verify if PA was approved prior to treatment and resubmit claim with PA number in REF*G1. If not obtained, file retroactive authorization appeal if permitted by payer policy.

## Specification Matrix
| Attribute | Value | Technical Guidance |
| --- | --- | --- |
| Reason Code | CARC 197 | Precertification / Prior Authorization Absent |
| Standard Group Code | CO | Contractual Obligation |
| ANSI 835 Segment | CAS*CO*197*AMOUNT~ | Loop 2110 or Loop 2100 |
| Balance Billing Patient | Prohibited for in-network providers in most commercial and Medicare Advantage contracts. | Compliance with billing regulations |
| Common RARCs | N54, N704 | Remittance Advice Remark Codes |
| Recommended Action | Verify if PA was approved prior to treatment and resubmit claim with PA number in REF*G1. If not obtained, file retroactive authorization appeal if permitted by payer policy. | Workflow for billing teams |

## Standard JSON Response Model
```json
{
  "transactionType": "835",
  "claimNumber": "CLM-2026-001",
  "adjudication": {
    "billedAmount": 500,
    "paidAmount": 0,
    "adjustments": [
      {
        "groupCode": "CO",
        "groupName": "Contractual Obligation",
        "reasonCode": "197",
        "reasonDescription": "Precertification / Prior Authorization Absent",
        "adjustmentAmount": 500
      }
    ]
  }
}
```

## Frequently Asked Questions & Edge Cases
### Q: What does CARC 197 mean on an 835 ERA?
**A:** CARC 197 signifies: "Precertification/authorization/notification/prior determination absent, or exceeded.". It explains why the payer did not pay the full billed charge.

### Q: Can a provider balance-bill the patient for CARC 197?
**A:** Prohibited for in-network providers in most commercial and Medicare Advantage contracts.

### Q: How do medical billing teams resolve and appeal CARC 197?
**A:** Verify if PA was approved prior to treatment and resubmit claim with PA number in REF*G1. If not obtained, file retroactive authorization appeal if permitted by payer policy.