Very CommonContractual Obligation (CO)Prior Authorization
CO-15: Authorization required but not obtained
The procedure or service requires prior authorization from the payer, but no authorization was obtained before the service was rendered, or the authorization on file does not match the claim. This is one of the most preventable -- and most costly -- denial codes in healthcare.
Common Causes
- Prior authorization was not obtained before the service was performed
- Authorization was obtained but has expired by the date of service
- Authorization number was not included on the claim
- Service performed does not match the authorized procedure code
- Authorization was obtained for a different provider, facility, or number of units
- Retro-authorization request was not submitted within the payer-required timeframe
How to Resolve CO-15
- 1Check if a valid authorization exists -- it may not have been included on the claim
- 2If authorized, add the authorization number and resubmit
- 3If no authorization exists, submit a retro-authorization request if the payer allows it
- 4If retro-auth is denied, appeal with clinical documentation and proof of medical necessity
- 5Contact the payer to verify whether the authorization covers the billed procedure/provider
How to Prevent CO-15 Denials
- Check prior authorization requirements for every procedure before scheduling
- Automate PA status checking so expirations are caught before the date of service
- Include authorization numbers in the scheduling/registration workflow
- Maintain a PA tracking system with expiration date alerts
- Verify that the authorized CPT code matches the planned procedure
Related Denial Codes
Stop Denials Before They Happen
Greenlight automatically checks prior authorization requirements and submits PA requests before the service is rendered -- eliminating authorization denials entirely.
See How It Works