Precertification/authorization/notification absent.
The payer required prior authorization before the service was rendered, and no valid authorization was obtained or submitted. This is one of the most preventable and most costly denial codes.
What This Means in Practice
CO-197 means no prior authorization was obtained. Services rendered without required authorization are typically denied and may be non-appealable unless retro-authorization is possible.
Common Root Causes
- →Authorization was never obtained before scheduling the procedure
- →Authorization obtained but not attached to or referenced on the claim
- →Service performed at a different facility than the authorization specified
- →Incorrect CPT or diagnosis code on the authorization vs. the claim
- →Authorization expired before the date of service
Common Billing Mistakes
- ✗Not checking if prior authorization is required for the service
- ✗Not entering the authorization number in box 23 of the CMS-1500
- ✗Not verifying the authorization covers the specific CPT code and number of units
- ✗Not checking the authorization date range
Documentation Required
Considerations
Modifier
No specific modifier applies to CO-197. The denial is for missing authorization, not a modifier issue.
Medical Necessity
If retro-authorization is requested, the payer will review medical necessity. Prepare clinical documentation showing the service was urgent or emergent.
Prior Authorization
CO-197 is the primary authorization denial code. Always verify authorization requirements before scheduling. Request retro-authorization if the service was urgent/emergent.
Eligibility
Verify the patient plan requires authorization for the service. Some plans may not require it.
Coordination of Benefits
If denied by the primary for no authorization, the secondary will likely also deny.
Timely Filing
Submit retro-authorization requests as soon as possible — typically within 24-48 hours of the service. Retro-auth success rates are 30-50%.
Appeal & Resolution Strategy
Appeal with the authorization number (if obtained but omitted), or request retro-authorization with clinical documentation of urgency.
Related CPT Scenarios
- ▸High-cost imaging (MRI, CT)
- ▸Surgical procedures
- ▸Specialty drugs (chemotherapy)
- ▸Therapy services exceeding visit limits
ICD-10 Considerations
The diagnosis on the claim must match the diagnosis on the authorization. Mismatches cause CO-197.
Related Payer Policy Guidance
Medicare
Medicare requires prior authorization for specific services. Check the CMS prior authorization list for your jurisdiction.
Commercial
Commercial payers have specific authorization requirements. Check the payer portal before scheduling.
Medicaid
State Medicaid programs have their own authorization requirements. Check your state Medicaid manual.
Related Resources
Knowledge Center Articles
Academy Lessons
Similar & Related Codes
Disclaimer: Code definitions and payer policies change. Always verify current definitions against CMS, X12, and payer-specific guidance. This information is for educational purposes only.