CARC 197: Prior authorization missing
The service needed prior authorization, precertification or notification, and the payer has none on file.
Group code context
Usually sent with group code CO (contractual obligation): under your contract you cannot bill the patient for this amount.
Common causes
- Authorization never requested
- Authorization obtained for a different code, date range or provider
- Authorization number not put on the claim
Step-by-step fix
- Check whether an authorization exists in the payer portal
- If it exists, add the number and resubmit
- If not, ask whether the payer accepts a retro authorization
- If not possible, appeal with the clinical reason, or write off under your contract
Appeal guidance
Appeal if the authorization existed, or if the service was urgent and the payer's rules allow a late request.
When not to appeal
Do not bill the patient under a CO denial. Fix the authorization workflow instead.
Prevention checklist
- Check authorization rules when scheduling
- Match the authorization to the exact codes, dates and provider
- Track expiring authorizations
Related codes
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Source and review
Official source ↗Last checked: 2026-10-05
Reviewed by: PracticeVendors editorial team
Educational reference. Confirm payer instructions and applicable contracts before taking action.