Denial Code Lookup
Search denial codes and learn how to resolve them
Search Denial Codes
Enter a denial code (e.g., CO-197) or search by keyword
All Denial Codes
CO-16
Claim/service lacks information or has submission/billing error(s)
Why This Happens
Missing required information on claim
How to Fix It
Review remittance advice for specific missing elements and resubmit corrected claim
Prevention Strategy
Use claim scrubbing software and verify all required fields before submission
CO-18
Duplicate claim/service
Why This Happens
Claim appears to be a duplicate of a previously processed claim
How to Fix It
Verify if previous claim was paid. If not paid, resubmit with corrected claim. If paid and this is a separate service, add modifier and documentation
Prevention Strategy
Track submitted claims carefully. Use modifiers 76/77 for repeated services
CO-29
Time limit for filing has expired
Why This Happens
Claim submitted after payor's timely filing deadline
How to Fix It
Appeal if there were payor-caused delays with documentation. Otherwise claim may be patient responsibility
Prevention Strategy
Submit claims within 90 days. Track submission dates and deadlines
CO-50
Non-covered services
Why This Happens
Service not covered under patient's specific plan or deemed experimental
How to Fix It
Review plan documents. Appeal with medical necessity if should be covered. May be patient responsibility
Prevention Strategy
Verify benefits before service. Obtain ABN for potentially non-covered services
CO-96
Non-covered charges
Why This Happens
Specific charges or services not covered under patient's benefit plan
How to Fix It
Check patient's Summary Plan Description. Appeal if covered. Patient may be responsible if truly non-covered
Prevention Strategy
Verify coverage details and obtain authorization when required
CO-97
Benefit maximum reached
Why This Happens
Patient has exhausted their benefit limit for this service type
How to Fix It
Submit medical necessity appeal for exception. Otherwise patient responsible
Prevention Strategy
Check remaining benefits before scheduling services
CO-109
Claim not covered by this payer/contractor
Why This Happens
Service may be another payor's responsibility or patient not eligible
How to Fix It
Verify patient eligibility and coverage. May need to bill different payor
Prevention Strategy
Always verify eligibility at time of service
CO-197
Precertification/authorization absent
Why This Happens
Required prior authorization was not obtained before service
How to Fix It
Submit retroactive authorization request immediately with medical records. Success rate 30-40% if medically necessary
Prevention Strategy
Always verify authorization requirements before scheduling services
CO-B7
Benefit maximum for this time period or occurrence has been reached
Why This Happens
Patient exhausted visit limits, annual maximums, or lifetime caps
How to Fix It
Submit exception request with medical necessity documentation
Prevention Strategy
Track benefit usage and verify remaining benefits before service
PR-1
Deductible amount
Why This Happens
Patient responsible for deductible portion
How to Fix It
Bill patient for deductible amount. Not a denial, just patient responsibility
Prevention Strategy
Inform patients of estimated deductible before service
PR-2
Coinsurance amount
Why This Happens
Patient responsible for coinsurance portion
How to Fix It
Bill patient for coinsurance amount. Not a denial
Prevention Strategy
Verify patient's coinsurance percentage and collect at time of service
PR-3
Copayment amount
Why This Happens
Patient responsible for copayment
How to Fix It
Bill patient for copay. Not a denial
Prevention Strategy
Collect copayments at time of service
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Denial Management Best Practices
Act Quickly
Most payors have 180-365 day appeal windows. Don't wait
Document Everything
Keep records of denial notices, appeal submissions, and all communications
Track Denial Patterns
Analyze denial trends to identify systemic issues in your billing process
Provide Clinical Documentation
Medical necessity denials require strong clinical justification in appeals